Open tabs, mails sent to yourself, printed papers. For articles you want to read, there is a better option: Readwise Reader.
On freeform structure, complexity, and data portability.
Obsidian plugins help with different parts of your knowledge work, and with different kinds of notes. Understanding those differences can help when deciding what plugins to use, and how.
In 2020, I found out about Readwise. And so far, it solves all three challenges with annotating and making highlights.
I'm willing to sacrifice both features and UX for the longevity of my notes collection. And right now, I only find longevity in locally stored markdown files, text files that can be opened in any text editor on any device.