I would love this! I was about to request a feature like this. Getting tired of setting up calendar reminders for 2 days ahead to accept my own answer.
I have posted several questions with answers of my own, Q&A style. I would like to remove any ambiguity for the reader as to whether the answer is good enough. Yes, it is good enough, and just like any other good enough answer, deserves an "accepted" checkmark!
Do you consider such an email as "noise"? Then this feature should be turned off by default in the settings. I will be happy to turn it on, and save myself some time later. :)
When you are writing a self-answer, it's almost always clear from the content alone that the answer provides an adequate solution and would be a candidate for the accept mark.
It is clear if your read the names of the authors of both the question and the answer. If they match, then you make a connection in the brain - and voila! It is clear. But who does this? Scroll back and forth, match, think! That's why we have the green checkmark!
The OP's own answer to the OP's question was not marked as accepted. Even worse, there are a few other answers, all with zero or -1 score, and nothing is accepted. What is this?
Maybe the OP abandoned this post (most likely), and it has been overgrown with weeds. Or maybe the OP meant to accept their own answer as the best one, but forgot. Or maybe they meant to accept someone else's answer. We may never know - without the checkmark, that is!