This is one of the main strengths of Obsidian, which I have been using lately and I’m extremely happy with: everything is just Markdown files in some folder on disk. Zero danger of lock in. You can have a disk hierarchy if you desire, or trust that search will find you what you are looking for. For me search works fairly well and if I need something extra I can just grep/sed/awk. Plus it has the features that a simpl…
Serious question: how do you square your third paragraph with your first? That is, if you're using Obsidian's features like [[square bracket link syntax]], or #tags, or inline images, aren't you effectively locked in to editors that support the same set of features?
Best practice for tags is just include them in the plain text file, and inline images in Obsidian is like Derek said — just keep them in your folder structures just like your text.