It makes literally 0 sense to force 2FA upon people. Big annoying warning that says "2FA is very recommended" it's ok, but not forcing it, there is a reason no exchange does that. I use public numbers to bypass SMS verifications all the time myself because there's no reason you would need to give personal data at that level to do that. Again, there's a reason you don't need phone verification in any exchange to log in and do basic alt to alt trading. Of course, when fiat is involved, it's normal to start wanting more credentials, but forcing people with phone verification alienates people to use your service.
If you live in a third world country, or lets say you don't have a smartphone (a LOT of people still don't), you can't use Google Auth which leads to being forced to check your phone every single time you log in. This is a big no-no.
Reconsider how you run this.
How does it 'literally make no sense'? It literally
does make sense because people lose their coins all the time and as soon as they do they bog down support with complaints asking where their coins have gone. And who are these people in the third world that don't have a phone but yet have the internet, computer and are actively involved in the crypto community?
Duh, about everyone that doesn't live in a first world country?
A lot of people can have easy access to the internet these days in public places. Even if that wasn't the case, If you are a guy living in a poor country that emigrates to a more advanced country, what is he going to prioritize, a cheap internet connection (if he can't find a public wifi which he always could) or buying a McSmartphone to use apps?
Why is this a big thing?
https://www.cryptocoinsnews.com/coinapult-bitcoin-sms-wallet-allows-world-send-remittances-just-text/Earlier today, Coinapult took to the Bitcoin subreddit to unveil their new, global Bitcoin service that functions on plain ol SMS technology. This means that users around the world that do not have smart phones or data plans will be able to use Coinapult SMS.
Again, this, and the fact this is the only exchange forcing 2FA on people are objective facts. It's all about having options. 2FA compromises your privacy when you have to give your personal phone number, people should have an option to risk less security for more privacy. Never in my life I used 2FA and I never lost a single coin, and i've used a ton of different exchanges and moved a lot of BTC. Why? because I take care of my coins. People should take care of their coins, get recommended to get 2FA on a daily if you want thought a popup message, but NOT force it.
Forcing things on people for the sake of security at the expense of a loss of privacy is exactly the same perverse argument the governments make.