I've been using what is essentially a single sticky note (Raycast floating notes feature) for a year now and it works great. I put todos, meeting notes, ideas, and everything else in there with zero organization. When I want to remember stuff I read it. When I finish stuff I delete it. Has worked for me better than Notion, Obsidian, Reminders, Tick Tick, etc.

I've found that for productivity tools, there is an inverse correlation between time it takes to setup and how effective it is.