Totally with you on a) the defintion of shipping and b) that it would not be narratively satisfying to have the show go in the Will and Mike get together direction, for all the reasons you listed.
The dialogue around it also makes it nearly impossible to find meta or even just discussions around Mike that don't centre the possibility of a romantic relations with Will and it's so frustrating. I love that little guy and I just want to talk about how much he loves his friends!
But then the first thing I created for this fandom was a byler breakup fic so... I'm probably not in the majority.
Anyway keep on trucking and I LOVE Robin and Steve's Epic Platonic Soulmate Mixtape <3
Ah thank you! Yeah. The series is grounded in the friendship the party has. That's the first thing we learn about them. It feels insulting to both the characters and anyone who likes the non romantic aspects of relationships when people insinuate that Will couldn't have a happy ending without dating Mike. (Mike doesn't owe Will a romantic relationship. Will doesn't owe Mike one!! It also feels insulting that people say there's going to be a time skip and I guess Will is still pining for him? Let him let go at that point Sheesh.).
The basis of any romantic relationship, especially in canon, between Will and Mike (or any party members) is a deep and strong friendship. Acting like those aren't as important is so rude to people and mischaracterizes them. Mike Wheeler loves his friends so much he would jump off a cliff for any of them. He would deny their death with the barest shred of illogical proof even when presented with a body. He would try to contact a girl for almost a year to see if she was still alive. He holds his friend's hand when it seems he's fading away, insists on going into danger to help with a distraction, and apologizes better to a friend than his girlfriend. He's a moody, angsty teenager, going through a lot of emotions and confusion, and can be an asshole even to his friends, but my god what are you doing if you deny Mike's platonic relationships mean everything to him.
It's also disregarding Will's relationships too! Like. El is his sister now!! You cannot separate that. Would Will want to date Mike even? Loving and wanting to date are different. Dating a sister's ex? Legit so many arguments are just saying El doesn't love Mike, and I guess implying she wouldn't give a shit if Mike stsrted dating a friend that became a brother who is also the only one as deeply connected to the Upside Down as her. It gives me the vibes of people like...taking away the agency El has in her own feelings and saying she loves Mike.
Maybe he just wants to be able to honest about his feelings. Get them off his chest. Keep his friendship with Mike but have everything out in the open, and they can work through that together. Strengthen their friendship and maybe be open to potentially dating in the future (there is an apocalypse on!) while also strengthening their friendship with El. So many people just. Ignore her and her feelings in all this, as though both Will and Mike have not showed they valued her feelings greatly. Why would that not factor in at all? Why would Will put his sister into that position? Would it not be awkward for Mike too?
That's why it wouldnt be satisfactorily executed in S5. The characters and the audience need time to process any breakup between El and Mike. Let them cool off and us register it. Another anon said if they were going blr canon route they should have ended mlvn in S4, and I agree. It needs Breathing room. Not just them breaking up and a two year time skip where we're told time has passed but for us it feels like nothing, so the impact isn't the same and it doesn't have the same satisfaction of knowing they've worked it out but just being told about it. If that makes sense?
Plus the series has struggled with ending romo relationships, and the only one starting that wasn't awkward or weird (Both Nancy and Jon AND Joyce and Hop have Murray be the catalyst which annoying and kinda lazy, not to mention the cheating) was Lucas and Max. That doesn't paint a picture of confidence in me. Sometimes a ship going canon is not actually good. Sometimes in fandom you are actually thankful a ship that honestly should have been canon by the end, or at least post-series didn't, because whatever the show runners would have done with it would have probably ruined whatever dynamic that made them compelling in the first place. it may feel like a betrayal or rip off at first, and would likely continue to, but with time comes a feeling of oh. Maybe it's better this way... Would come.
So yes. Seeing how people reacted to me simply saying that, by the end of the series, I don't think it could satisfyingly become canon, while prioritizing their relationships with each other, Not a lot of nuance is allowed, it seems. Though I'm sure many shippers are cool and chill, it's really just a few people who are loud about it that try to inhibit discussion or meta, it's a damn shame that the only discussion allowed to those shippers is when or how it will be canon. Where's the fun in that? Everyone can interact with fandom differently, and it's a shame some folks want to dictate how others do so.