Technically Markus and McFeely did since they worked on the first movie that the Russos had nothing to do with.
It's my favorite Avengers movie and I didn't hate the ending but I wish they got one last conversation at the end when Steve returned. Even if it would've likely killed the ship even further, these two guys who grew up like brothers deserved a proper resolution plus some clarification of the many confusing things about the ending, especially since the directors and writers can't seem to make up their minds about it. They might discuss this in the upcoming Falcon and Winter Soldier show but I doubt it. At the least I hope they make mention of Sam and Bucky talking about their friend Old Steve doing things offscreen and not bury him ungracefully.
Feels like they were downright scared of all the shippers and backpedaled because they thought feeding them would accentuate the backlash when they inevitably couldn't deliver. Except shippers who actually get mad purely because their OTP died represent a minority. Many of them, especially Asian fujos, prefer it to be ambiguous and care more about interactions than canon. They ended up pulling back so hard after making Bucky so important for three movies that it caused whiplash even to the official narrative about these two being besties and brothers and people noticed. "Why didn't these two talk more?" was a pretty common complaint among everyone in my circles including the Stony and nonshipper fans because they remembered how prominent Bucky was even with Peggy in the picture.
I'm a multishipper and a gen lover. I enjoy platonic Steve/Bucky and romantic Steve/Nat. And I look forward to Bucky/Sam. Steve/Peggy is the one canon MCU romance I love. But the bittersweet tragedy was what made it so beautiful. She learned to move on without him, while he couldn't from her. That was a bold characterization move, so him getting to have his cake and eat it too after all is sweet, but less interesting.