How do you think, did Sokovia Accords in Civil War actually reflect the opinion of the majority, or was it strictly politically-driven act, forced by politicians and only favoring politicians? I believe it's the second option.
Let's look at two POVs.
pov of an ordinary person, not an active participant of any MCU event. So, what does this person think of Avengers? Well, from what we know, Avengers never directly and vocally threatened anyone, never exercised their powers for political purposes of any kind, in fact some of them originally operated within the bounds of SHIELD, government organization. The Avengers only ever responded to threats, never caused them, EXCEPT for the Ultron situation and the whole Hulk thing (to be fair, Hulk may be the key factor here). So from this moment on this ordinary person may start to question Avengers, but that's only if they never took time to figure out what really happened. If they did, they'd knew that even though Avengers made a mistake with Ultron, or allowed the Hunk mayhem, their response was immediate, no delay whatsoever. How many politicians that you know own their mistakes and try to fix them immediately? That's what I thought. So, can we suppose that the majority of the population was very vocal about the Avengers signing the accords and against the team as a phenomenon in general? I doubt so.
now, the high-rank politician's pov. The Avengers, not an individual, but a whole group of extra powerful beings uses their power however they want. So far, they've only been responding to some objective threats everyone can agree on. What if one day the Avengers decide to investigate a corrupt state as an extra activity? What if one day Avengers decide your policies are a threat, just as supervillains are? If I'm guilty of any of this, I'd be pretty scared and for a good reason. Someone like Captain America will NOT be quiet if he discovers something like that. But people love Avengers, so you can't do anything. And then an opportunity appears, Avengers make two mistakes in a row. First, civilian victims in Sokovia, then civilian victims in Lagos... So, while you still have the chance you push the narrative that the Avengers are too dangerous and should be regulated somehow. Luckily, there is a good number of politicians who are scared for their positions just as you are, so the process of taking down the Avengers officially begin...
Obviously, I'm team Cap as you could guess. There's no such things as institutions. Institutions ARE people, and if there's a good reason to doubt people's motives, institutions they run can't be trusted as well. I'm not saying the Accords is a wrong idea. But I'm saying it's an idea corrupted from the very beginning, as people who suggested it only ever cared about themselves.