As a software and game engineer, KYC is very helpful to lifeban cheaters and make them cry

That isn't why its implemented though. Its implemented because its often a government requirement. Gambling websites usually have a similar sort of system in place, where you can only deposit/withdraw large amounts once you have verified your identity.
I'm not even sure how someone could cheat on an exchange.
As a software and game engineer, KYC is very helpful to lifeban cheaters and make them cry

No, not all of us are claiming that identity theft is a massive issue. Although, it definitely is an issue so we can't ignore that, but a proper exchange or any service for that matter should be storing this kind of information off the server, rather than live.
We are saying that users of these platforms should be thinking more about their privacy, and should be valuing it more. The fact that, selling on data is a lucrative business, is something we have all probably become aware of in modern times. How many times, have you received a spam phone call? Now, sometimes this might be by random, and the caller is doing a brute force approach, but often it can be because someone has sold on the data.
(it's not that hard to steal people ID cards and documents without internet, it's very easy... no need to hack a database, it's more easier to break your door or pockets than most servers over internet)
Ignoring the difficulty of this, which I don't believe is easy either online or offline. The fact is, when your data is compromised on the internet, its likely not just your details which have been compromised, but thousands or even millions of users, which makes it a lucrative business. You might be right that a physical theft might be
easier, but you're probably going to leave a trace if you aren't a Ninja. On the internet, there are ways of concealing your identity, things like Tor are probably used by criminals frequently, and that's probably why there are rumours that the government also host exit nodes, to catch them.
However, to get to my original point. Lets just assume your statement is correct, that doesn't mean we should just ignore the very real fact that servers, and data get compromised a lot more on the internet, this is simply because; its a larger target area. You likely, only know around <100 people that know your real life address, and most of them and won't be interested in criminal activities, but on the internet someone doesn't personally need to know you, they just need to know where the service stores their data. They don't need any personal connection to you, and thus there will be more malicious users, trying to steal data, than in a physical way. So, while it might be easier to get this information locally, there are far more people trying to compromise your data online, and therefore the chances of significantly more than in person.
You guys obviously don't know anything about security and programming, you may be an engineer in toilet paper.
Well, the original point of the thread has nothing to do with programming. Plus, the cheating aspect you bring up seems to be more likely to be encountered in online gaming, rather than a cryptocurrency exchange. Even then, they don't require KYC. So, if I was going to counter your argument of "anti cheat", then it would be many successful games filter out most of the cheaters without introducing KYC.
Besides security, and privacy are similar, but aren't the same. You don't need to know programming to understand what is, and isn't a privacy breach. Same as, you don't actually need to know programming to understand what is secure, and what isn't. In a work place, you usually have someone come up with the ideas of security implementation, via a simple, but concise explanation, and are usually referred to as a design plan. The expect one person, to come up with a sophisticated security implementation is, rather unrealistic. Most security matters are developed by many people, due to the complex nature or they are simply using existing libraries.
Securing any system, be it online or a local system is probably one of the most complex jobs in programming. Just think, how many bugs you have programmed in your life, well they might have not meant anything on the grand scheme of things, but in a security aspect they could potentially be exploited, so any security implementation is usually extensively reviewed.
You being a software engineer, doesn't necessarily confirm you understand the programming aspects of security either. Software engineer is such a broad term, and might mean you've actually never touched any of the security aspects of a program or one that an exchange might use, and to what level. Especially true, if you work within a team, and aren't doing it alone as you usually cover a certain part of the code. For example, you might be responsible for the verification aspect of emails, or the system which extracts the ID from the live server, removes it, and then deposits it somewhere else.
I couldn't possibly claim to know every aspect of security, that would just be absurd. Its why as companies we bring in experts in a particular field, and look for people with experience in a particular thing. Satoshi did a brilliant job, and is considered a genius within the field by many or if not a genius definitely a pioneer, but there was still bugs, vulnerabilities, and other exploits within his code. It definitely wasn't perfect, and anyone claiming to have a perfect system, is likely either lying directly or knowingly trying to mislead others to thinking that as you could never be 100% sure.
Like seriously, if you take a look at most companies out there, they've been exploited, hacked or breached. Google who employ top level people within the field for a lot of money, Bitcoin, Facebook, Microsoft, and this forum. They've all been compromised at some point, even when they have multi millions going into security. So, to go back to the original point you should be wary of putting your personal information
anywhere let alone places where their security budget is lower than average.
I'm not talking about exchanges / gambling websites but e-sport.
For the rest, i already know because i'm involved into defensive and offensive hacking since more than ten years, so it's not new, doxing cheaters and criminals is fun.
The KYC is evolving as the ID Card and all the rest, we shouln't stop to KYC just improve it.
We can already get your adress by hacking an e-commerce and it will be always the case. Honestly i could debate all your arguments but i'm just gonna tell you to learn some Security and Network engineering before replying to this.