I'm one of those people who won't believe Byler is going to be canon until I see it because this isn't my first rodeo and I know that just because it textually, subtextually, and narratively makes the most sense, doesn't mean it's going to happen.
My biggest concern was that even if the Duffers had planned a Byler canon all along, I doubted Netflix would allow their most popular show ever to be queer. And also because the GA loved midleven; they were iconic.
This is what makes it so strange that the Duffers were allowed to ruin them in season 4. And how Midleven is not being marketed AT ALL. If the reason for midleven being endgame is because it would be most profitable for Netflix,... then why aren't they cashing in??
And then I was watching this video essay by Verilybitchie on YT about Queer media which explains how oftentimes new companies (streaming platforms but also in the past just regular up-and-coming cable channels) would target minority groups because they're the ones most looking for new places to get content.
"In the 60s and 70s, when cable channels were first introduced, small new networks like Fox, and the CW, got their early success targeting niche audiences, specifically black audiences. (...) And streaming is following this exact same business strategy. They're churning out huge amounts of diverse content because they're building up a new business and they want to attract invested viewers who don't feel like they're getting enough content elsewhere. That includes people of colour, LGBT people, women, and young girls." - Verilybitchie
For example, one of Netflix' first shows Orange Is The New Black, is diverce as fuck. The main character is bi and in multiple queer relationships, and most side-characters are also queer one way or the other and ethnically and racially diverse. But it also targets women specifically; a huge demographic that isn't being catered to enough. This clearly helped build Netflix' userbase.
But now, with Netflix having become as popular as it is today, they want to target bigger, more lucrative audiences (aka predominantly cishet, white groups), which is why all of their shows are slowly becoming stale and mainstream or get canceled after one season.
But my point is that Stranger Things was given the green light in phase 1 - the phase where they were targeting minorities. This means that there's a higher chance for them to have been greenlit even if - or maybe even especially if - it was queer. And now with the panel saying "they were just amazed Netflix was letting them do this at all", I don't know it's just reminding me of all of this.
It's clear that Netflix is being very hands-off when it comes to ST, trusting them to deliver one way or another. Especially now re-watch value isn't as important in Hollywood anymore; they don't have to please the GA for it to remain popular, the GA will watch it either way until they figure out the queer endgame, and by then they've watched the whole show and ST will no longer be the reason for them to renew their subscription at the end of the month anyway.
If they hope to get a new audience for ST after the show is already over, so they can get a small boost of new subscribers, it would make more sense to once again target the queer audiences who wouldn't otherwise have watched it. Everyone who likes Sci-Fi Fantasy is already subscribed (or watching the show illegally) so they have to give it a new appeal if they want to get new fans; the queer userbase that will watch anything just because it's gay. In my opinion, it's their only way for getting new fans, especially once everyone knows how it ends and the suspense is taken away. And with shows like Sex Education, Young Royals, and Heartstopper doing as well as they're doing, they know there's a huge audience for this.
But more importantly; this brings more credibility to the Duffers having planned Byler all along, and with it being slowburn, and them only getting together in the final season, Netflix would have no reason to not allow the Duffers to continue doing whatever they want.