Time ago, as a stackoverflow user I was taught to accept the answers that I'd received when they were right.
I understood that it is really helpful when you are searching a question and also save time to other users that read the question trying answer them.
I think that SFSE moderators and users could encourage askers to accept answers when they are ok in the same way they are teaching users to ask properly.
I think that that is a good practice and a good way to improve SSE even more.
This is just an opinion.