I do bitcoin, ethereum, bnb and those three are the only ones I have majority of my money. I like to throw in 10 to 50 bucks to some lower level projects as well, if it is in the top 200 then I may consider as much as 50 dollars, but usually when it is silly and like 3435th coin type of very low level then I just throw in the 10-20 bucks I have in the metamask, and just hope that it will do well.
But that is like just 10-15% of my whole investment. Rest goes to just the three big names and I believe that they will not go down too much. This is how I hope that I will get better because I know that even though they are volatile, they will be great investments in the long term.
That is something people have been doing for a long time. The difference is that the common thing was when the prices go up, everyone makes a lot of money and during those periods people end up with making so much money that they throw away some of that money by investing into smaller stuff.
Of course that is not a common thing when you look at how frequently that happens, but it is a common thing that nearly everyone does it each time it happens. So, when you see prices do a 10x in a hyped period (like 2021) then you will see people invest 10-50-100 into silly idiotic stuff and make money from that. This of course is not that rare but also very risky.