In the past, there were indeed many skeptics about bitcoin, maybe if we were in the same era we might think the same thing. Moreover, at that time bitcoin was not like it is now and those who doubted its future, so it is natural for some people to say things like that.
I also believe that if it were us, we would have done the same thing, sold our bitcoins because investing in bitcoin at that time was not the same as it is now. Everything is vague, unclear and uncertain, so we cannot help but doubt or fear.
However, it would be better before making such statements, it would be better to first research why bitcoin was created and how unique bitcoin is that it has the potential to become a future asset, finally realizing that bitcoin will become a rare asset in the future.
The future is unpredictable, even satoshi at that time did not dare to confirm anything, so no matter how much we researched bitcoin, we were always skeptical at that time. It is human nature to be skeptical about new things.
If we talk about regret, maybe almost all past investors have felt that regret, why didn't we invest in bitcoin a long time ago. However, with that regret or from the regrets of others, we can learn not to underestimate something new that we don't understand properly and know that investing in bitcoin is never too late, so start investing in bitcoin.
Yes, we should take it as a lesson for ourselves instead of laughing at them because as you said, if we were them, we would do the same. Stories about selling bitcoin early or using 10kBTC to buy 2 pizzas are lessons for us, not stories to laugh at and ridicule.