However, I also believe it can be very helpful to know which answer was the most appropriate. Whether that is by TS or other more experienced members. I deem the best answer mod one of the better mods in that regards.
Ok, and who will decide for the best answer: ChatGPT, Bard or me? 
I quote myself "Whether that is by TS or other more experienced members"
But other Q&A boards usually let the TS do that. Only TS is able to decide whether the answer was good enough to solve the question/problem. Most people do not even bother though, as it is not mandatory to do so.
It all has to do with etiquette. Some people are raised up very neatly in that they take the time to create an account, dig up a 5 year old thread just to say thank you to the person that provided an answer/solution to a problem.