I have a similar thing, I was a semi-regular BuJoer some years ago but then I noticed that even though I did enjoy the physical action of writing stuff down - I forgot to write things down eventually. The time from idea to finding my notebook and the correct place to write something down was too long.
Now my system is geared towards minimal friction from "crap, I need to remember this" to actually storing it in Obsidian.
Currently I have a Keyboard Maestro macro that activates when I double tap the key on the left side of 1 on my keyboard, which then will activate Obsidian (or start it if needed) and brings it to the front with a QuickAdd dialog where I can write down whatever I was thinking about.
QuickAdd will then append it to an Inbox file with a timestamp. I might take a look at it later or maybe not, but at least it's written down _somewhere_ =)