Not only that, but PDFs embedded via <object> don't get shown in external apps in any browser. And this does in fact happen. For example, if you want to get your pay stubs or W2s via https://portal.adp.com you end up dealing with just such a setup.
I realize anecdotes aren't data, but this also applies to your anecdote; you're very much not a typical end user (starting with the fact that you're using Linux!).
I should note that "Netflix doesn't work" is probably a deal-breaker for the average user all on its own.