I put my markdown files in a Dropbox folder, so I can use apps like 1writer on iOS. Syncs well and works like a charm!
Whenever I have an interesting thought, I get my phone, open 1writer, it creates a new [timestamp].md file, and I just jot it down. It instantly saves to dropbox so if I open Sublime on my laptop, the file's already there.
On my PC, I mostly write in Sublime Text but now experimenting with Zettlr and Obsidian.
I heard heard other combinations with other cloud file services and other markdown writing apps work just as good.
Having a folder with plaintext notes going back years just feels ... future-proof.
I don't see how I could adopt a system that doesn't work on the device I always carry with me — the phone.