Okay, it's a teaser so there isn't a lot to go on but here's a couple of things.
One, the Eighties didn't look like that. Although it did in the commercials so I can give that a pass.
Two, I did like the tape-lines. It definitely gave it the air of something you wold find in an old video tape that turned up in the back of your closet.
Three, is the the big one. Steve (so rich this high schooler is driving a BMW Seven series Steve) is now slinging Ice Cream in the Mall, is he? That indicates a few possibilities.
The first is that Steve (and his magnificent hair) is now more or less acknowledged as the star of the show. It was supposed to be poor artistic boy with a heart of gold Jonathon (even though he is stalker). But frankly nobody ever gave a crap about him. Even worse, once Nancy dumped Steve for Jonathon nobody gave a damn about her anymore either. It makes for an interesting study in character development dynamics. I liked Nancy in the first series, she was layered and dynamic. I was actually worried about her when she got sucked into the Upsidedown. But in the second series she fulfilled her pre-ordained plot arc and dumped Steve for Jonathon. I lost all in sympathy for her character because of that.
Well that and her endless fucking moaning about Barb.
Jonathon, I never really liked at all.
Steve, on the other hand was the jerk character you were supposed to dislike and ended up liking more than the lead. Sort of like Alex Keaton (so long as we are being tot-tally Eighties here).*
He came into his own in the second series. Jonathon and Nancy's storyline did absolutely nothing to advance the plot and honestly the entire series would have been tighter if they had been lifted completely out of the story. He became, implicitly, the hero character and more effectively so than Jonathon was.
My assumption from the trailer is that they are now making him explicitly the hero character and lead. Why am I assuming that? Because they have decided to grant him the virtue of sudden poverty. Let's face it, thats the only reason he's gonna be slinging ice-cream in the Mall. Easy enough to do in the Eighties, his Dad's company gets raided and he loses his cushy job, then the whole family has to downsize their lives.
It's SJW law, you can't have the good looking rich kid be the hero. Good looking poor kid, that's just fine. It would be better if discovered he was gay and fell in love with a Body Positive Trans Black-Latino in a wheel chair but we can start with suddenly poor and work up from there.
He appears to have a new love interest who is girl. Goodness, he's not taking back that slut Nancy. Badness, his new girlfriend is going to have superpowers... Because all of the girls in this show except Nancy have superpowers.
*Being the jerk that people liked anyway was Michael J. Fox's entire career. Especially when it comes to Marty McFly, a character who had no story arc at all. If they want to reboot Back to the Future now, they should hire Joe Keery (aka Steve).