Hulk's strength has always been in the utter chaos he causes. He and Thor were fairly evenly matched in Avengers (and you could argue that Thor was stronger even then since he was trying to contain the Hulk, not wreck the hellicarrier) and Hulk remained at the same power level pretty much since then. The thing is though, Hulk has always said he is the strongest there is and fans of the Hulk have always been told he is the strongest there is, but that does not mean it is actually true. He's more akin to that kid you know who always boasted about how much they could bench press when other people could always beat him, they just didn't brag about it.
Thor may be more powerful but Hulk is still the absolute king of causing chaos. Hulk is more a bomb that explodes into more bombs that explodes into more bombs when used. Thor is the Avengers tactical strike and considering he's now imbued with the Odinforce (even if they haven't confirmed that yet) even more so.
As for Carol, I don't expect her to be the most physically strong. I do expect her to be the most "powerful" though and considering Captain Marvel's powerset involves energy absorption and manipulation, that seems pretty accurate.
TLDR: Power is not just physical strength, especially as the MCU gets more cosmic.
If you're referring to MCU Hulk, well I will say that I agree if we for a moment ignore the first Avengers movie. In the first movie, Hulk is considered so powerful that they don't even recruit him on the team because they're afraid they'd lose control of him. And when things go sideways, Hulk is the reason the good guys think they may win. Factually speaking, Hulk is the single Avenger that does the most damage to the Chitauri army and he's the one who stops Loki.
He's sort of the Avengers atom bomb, more powerful than the rest but too dangerous to use.
Then we slowly reach a point where he's just another guy and now he's a guy who's probably not even on par with Thor (or at this point possibly Iron Man) ON TOP of all the control issues. He's not the atom bomb anymore, just an unreliable gun.
Another thing I strongly dislike is that the MCU has become a bit like Dragonball, where people made of rubber are constantly punched into mountains or kicked into a wall and rolling around 100 yards tearing metal and concrete like it was cardboard. The idea that the Hulk's resiliance is something else (this is a guy who you can't really kill even with a nuke) would be that of having people punch him and him barely flinch. Instead he's kicked around like he was a giant inflated doll. He always stands back up, but ultimately most other heroes do too.
If we're talking comics, he's all over the place even there but he's the only Avenger Thanos admitted to be worried about. He's in a different weight category from anybody who isn't Thor, and Thor would never beat him in a pure brawl.