There has been a lot of past discussion about accepted answers and whether they should be, or stay, pinned to the top forever when there are better-scoring alternatives. (Maybe the accepted answer is bad or maybe it was fine then but things have changed and the OP isn't around to accept a better one.) Further, on some sites the accepted-answer concept isn't very useful -- it carries a lot of signal on sites like Stack Overflow, but "correct" is way less clear on sites like The Workplace, Parenting, or Interpersonal Skills. As one person put it on Mi Yodeya, who cares which answer the questioner thinks is best? On our site, we mostly don't.
Clearly changing this behavior network-wide in any way is controversial, and I am not proposing that. (See all the outbound links in the first question I linked, if you want to explore that.) Instead, can we allow individual sites to change it? Allow communities to say "for us, pinning accepted answers is a disservice" and stop doing it. On Mi Yodeya, in about 13% of question views, the accepted answer isn't the best (thank you Hugo Delsing for that query); our acceptance rate is also lower than expected, I think in part because people are reluctant to promote one among a group of valuable answers. Please allow everybody to keep the current behavior by default, but please let sites opt out, like we can for other settings like protection thresholds, meta rep requirements, and comment collapsing.
I think this option is of use primarily to the more subjective sites, but it's possible that sites around rapidly-changing technical fields might also want it. Let's let sites decide rather than trying to apply one set of rules to sites as diverse as Stack Overflow, Hinduism, Bitcoin, and Worldbuilding.