It’s worth pointing out that this scene WAS filmed on a actual set with actual asphalt and cars (with fall pads and stuff, but still). They really were interacting with their environment.
But as a fight nerd, there’s one other thing I want to point out about this fight, and it goes back to @mikkeneko’s point about the knife:
This isn’t a magic fight.
Yes, they’re both super soldiers. Yes, WS has a vibranium arm. Yes, Steve has a vibranium shield. But there are no magic blasts going on here. There’s no wuxia and minimal wire-work (mostly protective for the actors).
WS shoots at Steve until he runs out of bullets because that’s the most efficient way to murder him. Steve either dodges or hides his whole body behind his shield because that’s the most efficient way to not get murdered. The shield gets thrown, caught, thrown back, wedged in a car. Then it’s a knife fight. Throughout, it’s really obvious that neither of them are fucking around. WS is trying to just straight-up kill Steve, Steve is trying to not die. No banter. No dick-measuring. No quips.
This fight is brutal, efficient, and not flashy. Steve’s knife defense is textbook, and aside from that cool little flip that was almost too fast to clock, WS’s attacks are textbook. He’s doing his best to control Steve’s defense and open a hole to wedge that knife in. Steve’s doing his best to control that knife hand and keep just enough space between them that he can close those holes before WS can get to them. It’s telling that he’s paying so much attention to the knife that when WS finally gets through his guard, it’s with his empty, vibranium hand. (Still no idea why he tosses him instead of crushing his windpipe though, that was 100% movie logic.)
When Steve does that flying knee at WS, that’s not about flashy martial arts moves, that’s about brutal efficiency. Your knees and elbows are the hardest points on your body. Steve can engage in fisticuffs with normal people; he can knock out hitler over 200 times. He could also break his knuckles on WS’s face before doing any appreciable damage, and we watch him figure that out. So it’s not kung fu, it’s muay thai. It’s krav maga. Those flips aren’t for show - that’s pure Jiujitsu, the ruthless throws that are supposed to segue into joint locks and dislocations. That is the way to take your opponent apart, literally. He was trying to rip WS’s non-vibranium arm out of its socket.
That pile-driver? That was meant to break WS’s neck. A normal person would die instantly if Captain America pulled that WWE shit on them. We are into the gritty shit now. We have two extremely strong, extremely skilled men who are just trying to kill each other because the only way to win this fight is to die last, and it shows.
They scramble for position through the fight. When one move fails, they don’t bother breaking apart before finding the next-most-efficient killing move and trying that. This is what two people who are actually trying to murder each other look like - most street scuffles stay on the ground once they get there and don’t involve this much skill, but we can excuse that because it’s Captain America and the Winter Fucking Soldier. I still recognize the blocking of this fight as a real fight, not a spar. The urgency, breathlessness, the pragmatism, the messy transitions between moves as you just keep trying to improvise faster than the other guy… that’s all correct.
There’s no magic. There are fists, feet, elbows. There’s a shield and there’s a knife - the first and oldest human-made tools of war. There are chokes. There are joint locks. Not a word spoken. And it helps that they are really there - landing on cars, landing on asphalt.
No other MCU fight even comes close unless you’re including the tv shows, because that Daredevil long-shot hallway fight was pretty fucking badass too.