Some people say bitcoin is like gambling (my answer: they have no understanding of bitcoin and the more empty the brain, the more open the mouth)
You've started it wrong.
Bitcoin is still a risky investment. Just imagine how could have been feeling during 2018, 2019 and most of 2020 those who bought Bitcoin in December 2017 and you'll know what I mean. (Just imagine they may have needed the money in 2019!).
There are 2 types of saying for the same thing, depending on "optimism" (let's say it simple). "If you don't risk a little, you have no chance for (big) gain" and "If you don't risk, you'll surely not lose". So yes, for some, investing (especially the riskier one) is similar to gambling.
I agree that "empty brains" tend to have bigger mouth, but you may be forgetting that on internet and media some people say what they think, but also some others say whatever helps them (usually for various types of material gains).
The truth is always somewhere "in the middle".
Some say that the country should grow by investing in attractions such as the stock market (growth here can not be solved with money with its first education and learning)
On the road to success, they always make fun of you first.After you succeed, they realize that they are wrong and in the end they regret it.
I remember that a very young colleague at work told us (years ago) that he's investing in stocks. That's rather unusual here, at least for so young people, hence some smiled or even tried to mock him a little.
Now imagine the reaction on Bitcoin investments!
People are much (much, much, much) more reserved about new things than they want to admit (or acknowledge!).
In the end, bitcoin has grown, but there is a lot of room for growth.
I'm not saying to put all your money to sleep in bitcoin, but one day buy the size of a Satoshi dollar, then we will understand that you did the best job.
It was "a hell of a ride", and may continue to be so. It's not for everybody.
Hence the general rule "only invest what you afford to lose" (again, quite similar to "only gamble what you afford to lose"!!!), because in case you buy just before a bubble ends, you may sell at a loss or keep the money locked for longer time than you'd like.
And there is little way for bitcoin to become an everyday currency, because bankers and governments, because they have emptied people's pockets by printing unsupported money, do not want currencies like bitcoin to enter the cycle.
We'll see. Let's not predict such things. Central banks are close to issuing own stable coins. If the system gets used to them, Bitcoin could easily "get in", as something international, as something that cannot be devalued by certain country's decision. Of course, for that to be achieved Bitcoin price will have to stop bouncing like crazy in all directions