With respect, do you see currencies just consed up out of thin air as free of the avalanche of negatives you mentioned?
And I don't see fiat that way because:
1. I use if every day. It's widely usable as currency, it's inflationary, and its value doesn't fluctuate wildly.
2. Fiat only ever promised to fix the problems with gold, and it did that (in the US and Europe at least). It didn't ride a wave of hype that it couldn't live up to.
3. No one's hobby is talking about fiat. They don't harass me when I say I don't think it's interesting. They don't talk about the world falling apart and fiat plucking us from the ashes.
Fiat, The Fed, and active monetary policy are certainly criticized from all angles. I never said otherwise.
Stock is ownership of a company and entitlement to its profits. If you gamble on an unprofitable company with no assets, then sure, your stock could be worth very little. But even then, the company likely has cashflow or something in its financials that's valuable.
Companies selling stock are also analyzed to death and publish their audited financials.