wish that comments on old posts would not be locked.
That's double-edged sword.
On once instance, i get what you're asking, having solution(s) all in one topic.
But on another instance, that makes single topic, pages long, with hundreds of replies and finding the actual solution in that topic is difficult, especially when people are constantly replying into it, thanking for solution or asking for a solution, since they didn't bother to browse through 10+ pages. That, and with long-running topics, keeping the discussion on-point, without derailing into off-topic, is very difficult.
There is no good solution for this problem. But i find that the current order of TH forums suffices. Whereby, when solution is found and topic marked as Solved, it is closed. And it is up to new person, either to find the said topic with the solution or making a new topic asking for same/similar solution.
Making many people search for solutions faster
Due to the nature of people, very few are actually searching the answer within forums, combing through hundreds of topics. Instead, when someone has an issue, they want it fixed ASAP and they make a new topic with their issue.
Open forum search, use
asap
keyword, check the
Search titles only
box and look how many topics you'll find.