Whenever I want to put something down, I open the browser on my phone, type in the address bar, then hit <CR>. Later I synch them along with the other tabs when I have access to the desktop. This routine developed totally unintentionally and has been somehow more productive than all the fancy notetaking apps I'd used. Maybe it's something about the claustrophobically tiny input slot that makes me want to widen it as much as possible. Another bonus is that when I later get to format the long string of text that is synched (as you can see I don't believe in the paragraph when writing on my phone), I get loads of additional ideas.
> I have access to all of them on my phone via Files app and the iCloud sync
TIL that "unsaved" TextEdit files automatically go to the iCloud/TextEdit folder! That changes things for sure. (It also means that there is no such thing as an unsaved TextEdit file.)
Have you given Stickies.app a try? It is designed exactly around this model (notes are never "saved" in a true sense, they just live all over your desktop, what you can do is export / import text however).
> Whenever I want to put something down, I open the browser on my phone [...]
I write a mail (usually subject only) to myself. Actually, to noone, because my mobile devices Bcc myself. The notes are accessible from any device I can access my mailbox with, with no additional tools or servers for note keeping needed.
I've started using https://tot.rocks many months ago, which is basically a dot in my menu bar, and if you click on it you have 7, non resizable text views you can cycle through for small drafting. It's way more useful than I thought it would be and I use it all the time to quickly write down things during a meeting, my list of things for the day and other stuff that I can wipe at any time.