> The process of writing a high-quality question, with a minimally viable example, clearly lined out thought-processes, and other things tried, solved the question for me in most cases without me ever having to post it.

Nevertheless post the question and provide an answer. Everybody wins: you reap the upvotes, and everyone else benefits from the shared knowledge.

"marked as duplicate" pointing to a 5yo answer with links that 404

An answer relying on links rather than its own text is actually against policy, and should not have stayed up.

Unfortunately, there is a moderator strike now so I can't tell you to flag such an answer...

You don’t mark answers as duplicates, you mark questions as duplicates. And if it’s a duplicate question, the new answer should be posted to the old question. So it’s correct to mark the question as a duplicate. Otherwise all the people arriving at the original question won’t see the new answer.

Upvotes are worthless, and SO is unnecessary in this flow. Write a blog post or a gist, don't deal with SO mods.

Pretty much, yeah. Forgot about that term despite only encountering it in a novel 2 days ago :D