When it comes to bug reporting you usually wont see updates from Twitch on the subject either. The issue will be passed to the appropriate teams, given a severity and place in queue, and you may not hear anything back until one day whatever the issue is it’ll just be fixed, so just because issues on Github haven’t been updated doesn’t mean they may not already be in the process of fixing, or already fixed.
As for PubSub docs not mentioning token type, there are many places in the docs where the difference between User tokens and App tokens aren’t specified because it’s one of those common sense things implied by how tokens work, this is not just a Twitch thing, it’s standard OAuth usage with if you want to access user info, you need to explicitly ask that user for permission to do so, where as app tokens don’t require any user interaction at all. I’d have to double check but I’m pretty sure the docs do explain that App Access tokens for server-to-server requests, and not for anything on behalf of a user such as accessing their private data like email, subs, etc…