Man, that’s regret. And regret happens mostly for things or situations we don’t undersrand but imagine.

And in a way regret is judgement. ‘Those who judge don’t understand. While those who understand don’t judge.’

In a way ‘you wish yiu had that mindset then’ sounds like you wish you were grown and experienced’ when you were still young and learning. Not possible.

https://medium.com/illumination-curated/the-structure-of-regret-efddfc07158e