I get what you're saying though I'm not sure I fully agree that it truly "locks you in" - principally because the plugins are, unlike Obsidian, source readable

I get what you're saying though I'm not sure I fully agree that it truly "locks you in" - principally because the plugins are, unlike Obsidian, source readable JS files. Meaning worst case scenario, you could just adapt these plugins to a different ecosystem. Markdown transformers/parsers are relatively easy to write. Case in point is I have a custom obsidian plugin that converts a markdown note (related attachments) into a HTML ready for a static site generator. I will agree this is likely beyond the "ken" of your average user though. But I guess it really depends on the plugins you use. On a quick glance I have Admonition, Another Quick Switcher, and Mousewheel Image Zoom installed. Most of these are "renderers" rather than extending the regular markdown format.