Profits are the floor, as I mentioned. Negative profits in the absence of growth means the floor is 0 and the company may go under. That a stock can go to zero does not mean there's no floor under the price, but it depends on the company as to what that is.
Crypto has not gone all the way to zero. It went from $3T mcap to ~$800 billion. Despite over a decade of people predicting Bitcoin would go to zero, it's still $20K+ per BTC. Yes, down from the $68K euphoric highs of 2021, but substantially higher than its average price for most of its history, and on par or better than many stocks have performed this year.
Ordinary crypto currencies like BTC & ETH can't go bankrupt. They never had any liabilities to begin with. The majors such as BTC & ETH have deep, global, 24/7 liquidity. If you can find a way to make all the liquidity pools dry up for crypto around the world, I suppose it will go to zero. Good luck with that.
The entire stock market has also not gone to zero. You're comparing apples to oranges. Individual coins have gone to zero, as have individual stocks. It's irrelevant to the argument I made.