Totally agree. ETH is a good alternative to BTC.

Bitcoin cannot be a threat to USD, Pound Sterling, or any other conventional currency. Not in the next decades, at least.

Bitcoin cannot replace fiat because Btc lacks some important features for that:
- stability;
- paper form for offline transactions;
- is not backed by gold.

$3000 is the threshold for me. As soon as it reaches $3000, I believe, I'm going to sell it asap.

I agree. It's not that "dangerous" if you know the basic security rules to work with it.
Fiat could be too dangerous, too. For example, in many cities, if you go for a walk with a lot of cash in your pockets in certain neighborhoods, you might even get killed. That's how dangerous fiat is.
So, instead of saying it's "dangerous," read the security rules first and you're going to be fine.

I feel, in fact, bitcoin/cryptocurrency are beneficial for everyone because cryptocurrency represents technology that is supposed to ensure the transparency, reliability, low-cost transactions, anonymity, etc., etc.

This is a pretty tricky question in that it requires some background knowledge to get the idea of what the basis for making decision regarding investment is.

If you are interested in details, I recommend reading the following article from Forbes which might prove helpful in making your decision:
https://www.forbes.com/sites/bernardmarr/2018/02/05/what-is-the-difference-between-bitcoin-and-ethereum/#5833e61d7c70

For those who don't like reading a lot, here's a quote I find useful:

"... Ultimately, the long-term growth of any cryptocurrency (or indeed business) depends on useful applications being found for its assets.

If Bitcoin goes on to become a widely accepted form of currency, or the Ethereum network becomes an established standard for distributed computing, then the value of these assets is likely to continue to grow.

On the other hand, in technology, there is always something snapping at the heels of the front-runners. Newer and more efficient algorithms could replace either Bitcoin or Ethereum.

Additionally, both face the threat of government regulation. The value of many cryptocurrencies (including Bitcoin and Ethereum) have moved downwards since the start of the year, which has been attributed to threats of their trade being regulated by governments in China and Korea..."

Hopefully, that might help

Of course, lots of people are aware of cryptocurrency as a fact: it has been discussed for years now, BUT....
I wouldn't go so far as to say that the world is ready for crypto because there are still a lot of people who don't understand the nature of crypto and, as a result, are scared of it. And in order to be ready to accept it, one must understand what exactly what it is and what they options are. I believe we will see the time when crypto becomes commonplace, but we need to wait for quite a while before it becomes a reality.

Well, as you know well, the crypto market is one of the most unpredictable out there meaning you can expect anything and no one can tell you precisely what to expect just because there are way too many factors to be considered and some of them are out of a traditional paradigm.
So, all we have to do for now is sit tight and hodl. Being patient is our key to success now.

I believe, the reasons are pretty obvious even for such conformist organizations as banks: they have started seeing their apparent benefits.
For instance, the transaction costs even for large amounts are meager as compared to the standard banking rates. The security and reliability of the blockchain is like a dream come true for the banks, so no wonder they are willing to adopt it.

This is funny to ask a question like that in this community because everyone should be aware of security issues inherent in crypto. However, I was really surprised to learn that some of the people engaged in crypto world leave their coins online...
Me? Never will I leave my coins anywhere but in my cold wallet with key phrases being kept off-site in several trusted locations.
Cold wallet: Ledger Nano S, if you are interested.

What a surprising news! Never thought about it this way... Thanks for letting us know.
Here's the link for those who might get interested:
https://finance.yahoo.com/news/samsung-smartphones-most-secure-device-210755787.html?guccounter=1

I am Idealistic and against Banksters 

What a great night! I just read about Thailand legalizing crypto, and -- bam! -- South Korea has started taking care of the crypto! The world seems to be gradually facing up to the fact that cryptocurrency is a matter that can no longer be ignored

Way to go! The more countries accept crypto, the better for us! 

It depends on what exactly you want to get in the long run.
Whereas trading could be more profitable, hodling is more secure. So, it's up to you to decide what to choose
However, considering the fact you ARE here, maybe you should give it a try.
Either way, you will learn something...