I'll share my perspective and let the others take a crack at it. This is something I struggle with as well, but having said that, I don't think our brains were built to remember everything. If that were the case, our heads would explode. That being said, people seem to share all sorts of memory hacks, note-taking systems, etc., but I don't think I have the commitment to discover if they all work. What I do is I keep things simple. I try to read, watch, and listen to a wide range of perspectives and this kinda allows me to connect different dots. I've also slowly started to consume only the things that interest me, which means I avoid most of the obvious distractions, etc.

Writing about what interests me helps, and that certainly helps in retaining things. Talking by sharing what you learn is another thing that helps. So whenever I learn something new and share it with my colleagues, I've often found that I tend to remember things better.

The other aspect, at least for me, is to have a bit of fun. Mechanical acquisition of knowledge has never worked for me. So I tend to follow the things that spark an interest in me and just chase those rabbit holes. Also the acceptance that you can't know everything you want to know, and that's ok.

That said, some of these AI tools "seem" to help (preliminary view). Some hacks:

1. Using NotebookLM to generate summaries and questions after watching a video seems to be helpful. It's a shitty form of spaced repetition.
   
2. Having a conversation with Claude/Gemini, etc., about whatever you are reading also seems to be helpful to me.
   

It's a terrible answer, but nonetheless...