> Obsidian plugins have full, unrestricted access to all files in the vault.

And how exactly you can solve that?

I don't want to press 'allow access' on the every file some plugin is accessing.

One of the large dependencies they call out is an excellent example: pdf.js.

There is no reason for pdf.js to ever access anything other than the files you wish to export. The Export to PDF process could spawn a containerized subprocess with 0 filesystem or network access and constrained cpu and memory limits. Files could sent to the Export process over stdin, and the resulting PDF could be streamed back over stdout with stderr used for logging.

There are lots of plugin systems that work this way. I wish it were commodofied and universally available. AFAIK there's very little cross-platform tooling to help you solve this problem easily, and that's a pity.

Specific permissions declared in a manifest much like browser extensions could be a good first step.