I think a way to resolve things like this is to have media features.

For example:

  @media(prefers-user-select: all){ * {user-select: all;} }

But that wouldn't guarantee you could select text on an interactive element, plenty of other things could prevent it.

If it was an established known issue, then maybe people would do something like:

   :not(:lang('base-lang')) { * {user-select: all;}  }

It looks like there are plenty of extensions for this:

- https://chromewebstore.google.com/detail/user-select-all/aoh...

- https://chromewebstore.google.com/detail/enable-user-select/...

- https://addons.mozilla.org/en-US/firefox/addon/select-like-a...

- https://addons.mozilla.org/en-US/firefox/addon/user-select/