1. It true since the argument about formats. You can limit storage of open format to the cloud as well.
> and newer releases of certain apps remove the export functionality.
Then you'd just use the old release with the export functionality intact. You can also make up stuff like "Obsidian can release an app that deletes/encrypts all local files, retaining only the cloud copy, and start charging for it without having any export functionality"
> But I don't think you can credibly claim that a textual format like markdown isn't easier to parse than... well, almost any other format.
This isn't markdown, but markdown + dozens of extensions, so it's very easy to claim that it's much harder to write custom parsers for dozens of formats rather than use an existing parser for some more elaborate format that doesn't need those extensions.
> the files are stored in simple-to-read Markdown
they aren't, they're stored in an undefined format depending on which extensions you use. Part of it is markdown (which is not simple to read in the non-primitive case of richly formatted docs)
> there's no separate export
That's not a benefit! It means that you can't move outside of the Obsidian ecosystem because there is no well-defined format that you could use another app with! So it's (practically) even worse than Evernote since that one is already widely supported, though theoretically it's the same.
> But pretending there isn't a tradeoff is quite simply wrong.
Yet you've failed to identify it, turns out it all "depends on the specific app"! Fine, compare apps, but the general argument was about text-based proprietary format with a chance of data loss if the ecosystem dies (or a chance of requiring a lot of effort to convert), and a generic proprietary format that can be exported into a text-based format... with the same risks!