This market is anything but stable.
There is so much room left to grow.
We haven't even seen real money get involved.
I think the time for millionaire trains is gone. You have to consider the risk/reward ratio.
For example 4 years ago with a small cap coin it was easy to put 1000 $ on a coi and hope for the moon... if not, you had lost somenthing, but the moon could happen
Nowdays it's not possible the real btc moon like ETH or bitcoin was in their era...
I am looking into intersting projects, each coin is under 1$ but due the big market cap I can't see any moon out there..
IMO you're completely wrong. This market could grow 10x in the next however many years quite easily. Guaranteed there will be enough coins that have new technology, ideas, whatever that will blowup. Finding them, buying them, holding them, that's a different story, but there will be more.
As for the "time for being a millionaire, I would say a lot of people with 5 figure portfolios right now could easily be millionaires in the next 5-10 years. That's a lot more than you'll get keeping a 5 figure sum of $ in a damn bank.