Here, I think you can
As a personal viewpoint, peer pressure shouldn't prevent you from revealing new shines of truth, 'specially on something community-driven. But this is a personal opinion, not this community rules, hence I'll refer to the edit privilege help page instead :
When should I edit posts?
Any time you feel you can make the post better, and are inclined to do
so. Editing is encouraged!
Some common reasons to edit are:
- to fix grammatical or spelling mistakes
- to clarify the meaning of a post without changing it
- to correct minor mistakes or add addendums / updates as the post ages
- to add related resources or hyperlinks
As far as I understand, you aren't changing the core meaning of your answer (you still use dawns/sunsets to determine if the planet is flat), so adding an addendum could be a solution to your conundrum. Just tell this at the end explicitly this is a recent update of your answer (e.g. : "EDIT Aug. 2022 : I rethought on my answer and with my new knowledge I'd like to tell it's more subtle than what I intended/thought"). Telling that in second thought -even if it's quite late ^^- your answer has some caveats to consider is much more often than not an improvement.
If you happen to change the core meaning too much...
Sometimes you just feel your answer is just plain bad and want to take a whole different approach at the question, for instance you want to talk about winds instead of sunsets in your answer. Then, I'm not so sure whether it's a good idea to edit it. Well, unless there's a very defavorable feedback on it1.
Indeed, it's going beyond "correcting minor mistakes or adding addendums", and people who have voted up have done it because they genuinely think it's a (very) good answer, something you're not really sure your entirely new draft will improve. It also makes it harder for the asker to find what content they accepted -they need to look into answer's history-, if they happen to dig through their archives.
But this doesn't mean the end. Instead, you can always write another answer with this different approach. While it's not removing the accepted/high-voted answer from the lot, it gives a counterweight, something people with the same issue will take the time to read. You can also add a comment redirecting to your new answer telling to look at your new solution, e.g. : "My answer was written in 2016, and I think it's not as good as the new approach I've taken on today. You can find my new answer here (+link to answer)."
1 : ... Or if you feel very bad about it : I'd rather have someone happy than an answer to a question. But then deletion is perhaps better, perhaps.