Yes, it depends on the mail provider.

What is easier and better for your nerves? Moving to another mail provider or getting worked up for years?

Or if moving is not an option: how about stop wasting time and nerves on it? Just accept that your mail address doesn't work everywhere. There is no possible uture where you will force everyone on earth to stop mis-validating email addresses!

And I've never disputed that the problem is legitimate. I actually said in my comment!