Thanks for the link. Interesting conversations and anecdotes.
Don’t worry about the fact that you don’t understand anything. Just keep trying to get results. If you focus on getting results, the understanding will come to you naturally. It’s how I learned ML.
Watching presentations is nice, but tinkering with working code is so much nicer. It’s no surprise you came away feeling like you don’t actually know what you thought you knew — the only way to understand it is to go get some experience.
Also don’t worry that it takes a long time to understand something. This stuff is inherently hard. (My answer to your post is “Yes, of course I feel that way too! I don’t understand a damn thing in most presentations till I go code it myself.” So don’t feel alone!)
https://news.ycombinator.com/item?id=31044118