All this is mostly not about one piece but other series which I keep reading.
Don't care about others, I remember when I used to read in kissmanga(mentioning because it was high here, a bit sad that it's gone though I stopped reading there long back, just used it as a way to keep track of what is released) and trying to seek some good opinion/theories of any certain chapter(not one piece), the only thing I see in the comment is stupid(and some very insensitive) sex jokes on characters which even involves kids too. like wth, I used to reprimand them..but soon realized they could just be immature kids(regardless of age) who think talking sex-related things on the internet make them seem like some net veteran or something, and stopped reading comments whether I wanted to know any answers or not, eventually I would try to find answers someway which did not make me not enjoy.
I do still sometimes feel sad that certain series/character is so good, but people are not looking from the right perspective(again not about one piece) and used to explain it. I stopped doing that too, and right now just read the manga and get to solve things myself. I did enjoy talking with few unknown users about some series, but I guess I have to sacrifice a bit to make sure my experience is not ruined by other readers. Right now my interaction with other readers is pretty much non-existent.
Coming to one piece and the forum. I guess, from orojackson itself it was pretty clear the Sanji vs Zoro thing was atrocious in this community, even now we can see some guys just post to trigger each other. I am a Zoro fan, but that is more of an obvious choice for me, Sanji(who never even was on my likable characters except for few scenes) just fell down so hard in my eyes as a character that I pretty much had so much hate for the oda. And other SHs were also not being given attention. The other one is Nami but pretty much all females are now just fanservice material for oda, another disappointment(all are pretty shitty characters right now). I don't mind memes, but it's pretty clear some guys just heavily breathing on their keyboard waiting for an opportunity to make posts to trigger the other.
In orojackson, I used to make many speculations and threads too, but here I joined when the website was started(around the time when orojackson was going down), but I just did not feel like being part of the forum, so did not open the forum for like 6-8 months I think. Even lost interest in one piece and don't make any speculation or thread, but it could also be because I don't really care about anyone here to share my interests with specifically by making a thread, the most I will do is add a comment and make memes. I started feeling I guess this forum only deserves to have some memes unlike what we had in orojackson where speculation/theories and threads were very fun to read. This might seem like a comparison, but I guess it's fine since it gives out the points too. Just go through the threads here, and you can how shit they are.
So the best advice I can give is
Don't care about others, don't read or ignore their opinions, will take some time to do that but will eventually happen.
If you think you have some like-minded people here who you would like to talk to and enjoy, make a private chat group instead and enjoy it. Well this tip may not work for fans who want to trash talk on other characters since their aim is hurt the characters fans.