Your past self wasn’t stupid. They had less information and fewer people in their corner.

Looking back at a decision you would not make now feels like looking at somebody foolish. What changed is mostly input: you know how it turned out, you have met people who explained things, you have had years of small corrections. The person who made that call had none of that and was doing their best with what had reached them.

Pick one thing you still cringe about and write what you actually knew at the time. Notice how reasonable the choice looks with that information and no more. Then ask who is in your corner now that was not then.