

You’re missing one massive issue here, which is that - irrespective of the version you think you downloaded - they can use this tactic to force the latest version to be installed instead.
Need an older version, because they broke a feature, changed the license terms, made something that was previous free paid-for, or otherwise? Too bad. That installer is only ever going to do one thing, and it’s the newest version (if, as you say, it continues to work at all).
That’s “missing” as in “an additional problem that’s not on your list”, I brought it up as it’s one I’ve run into myself with online installers; not actually delivering the version of something that you’d asked for.