It may simply be that the intense disruption of a 5 hour long experience of chemically-induced novel pleasures - in people who'd long forgotten any form of enjoyment at all - while also being under special attention from caring professionals, is Very Nice Indeed. And that very nice experiences are the most direct salve that exists, when it comes to ameliorating a lifetime of unpleasant ones.
"I can say wth certainty that I became a very different person at some point in those early to mid twenties" - not to discount that, but I do suspect many developing adults (LSD or not) might make similar claims about distinct periods of mental change as they work their way into early adulthood.
There’s more evidence it is than it’s not. And, yes, even people who have been super stubbornly against psychedelics only very seldom come to regret taking some. Which you cannot say for other recreational or sedating stuff at all.
According to the GPTs, the LSD ranks the bottom in the chart of ‘damage done to your organism’ while alcohol tops it every time.