I don't think every list of disposable email providers that incorrectly includes ProtonMail deserves a post to !technology@lemmy.world. Lists that are widely used deserve that kind of attention, but this has two stars on Github.
As BombOmOm points out, this list includes free email providers and the inclusion of ProtonMail is correct.
It's a list of places you can get free, disposable email addresses. Protonmail fits here. Now, why anybody would use this list for mail filtering is a whole different question. They'd be blocking some huge email providers.
This is the second thread I've seen like this recently. Proton made a properly labeled throwaway github user to open issues on every repo with anti-abuse lists that contained their domains a few weeks ago. Now different throwaway users are opening new issues for the repos that declined to remove them and then posting to social media trying to rile up an outrage mob to flood the issues. Seems super sketch. Yet another reason to stay away from everything proton.