This can get you flamed, and in a way rightfully so, because you just made the author do more work for seemingly no reason. If no one else regularly has a problem integrating, being That One Person https://xkcd.com/1782/ is a great way to declare that you're hard to work with.

Then you find that GitHub forbids multiple identity contexts for free accounts in their terms of service ("One person or legal entity may maintain no more than one free account"), so if multiple people want you to do things on GitHub but you don't want to mix the activities together, your options are to pay for a monthly subscription (possibly forever) or break the rules and hope your ability to continue participating doesn't suddenly get taken away if they catch you.

Centralization of interaction by type creates social paradoxes like this.