If you were reasonably confident the stock was overvalued and/or would go down, why would you not short it, (Or similar)? "Talk is cheap" and "Putting money where mouth is" are both trite, but applicable here. In the short term, this can misfire, but as a consistent mindset long term, it would expose whether there is value in these assessments.

To help you understand my mindset here: Picture a simple game or bet. RNG/dice etc. 55% chance for a $10 payout; 45% chance to lose $10. You would keep on rolling that die, right? I believe this is is close enough of a comparison.

Stated another way: Someone else who has no confident predictions about the market and is in index funds or similar, would love to be able to make confident statements about a stock (SPCX or w/e), because it would be an effective edge. They wouldn't just post about it on the internet; they would take appropriate positions.