Linux

Personally, I've kind of given up all structure.

I have a script that creates a Markdown file with basically just the date in the file name and then it opens it in my text editor. All Markdown files are in one big folder. Notes, todos etc. all go into the there.

So long as a file is open in my text editor, it's actively relevant. Afterwards I'll use full-text search (like grep -iR), if I need something again.
I will often specify a title in the Markdown, but mainly because it's a great place for keywords to make the file easier to find again. It's also my way of tagging the files.

I mainly like this way of working, because I spend very little time on inputting information, which I do way more often than retrieving information (at least for the files which aren't actively open in my text editor).
But I've also never used a structured approach for more than a few months without it turning into chaos, where full-text search is the only option anyways.

Maybe this would be different, if my tasks were more structured. Your mileage may vary. ¯\_(ツ)_/¯