I guess back with The Marvels, it's aligned with the Disney money-printing machine. The Marvels is budgeted for $225-275 million range. This typically does not include advertising. (It was only supposed to be $130 million originally but ballooned with reshoots and whatever else.) The variance above supposedly comes from the production costs being $275 million but there was a $55 million dollar stipend from filming in England.
For most companies this is a ridiculous budget, but the MCU was getting away with these $200 million film budgets because their returns for quite awhile was in the $800-1.2 billion dollar return and even a lot more for some of its best films. (Endgame pulled in what, $2.8 billion raw box office, on a $400 million budget?)
Basically their return was so high that they could just throw money at the budgets because they knew they'd get it back.
I don't think since Endgame this has been nearly the case. The Eternals had a $200 million budget and only pulled in $375-400 million from the box office -- and is considered to have overall lost Disney $35-60 million. The worst returns during Phase 4+ might be worse than the first few films released within the MCU before it became a juggernaut.
Spiderman FFH: $160 million / $1.132 billion
Black Widow: $200 million / $375 million
Shang-Chi: $150 million / $432 million
Eternals: $200 million / $401 million
Spiderman NMH: $200 million / $1.9 billion
DS2: $200 million / $952 million
Thor L&T: $250 million / $760 million
Black Panther 2: $250 million / $853 million
Ant Man Quantumania: $200 million / $463 million
GotG3: $250 million / $845 million
Basically the beloved character stuff with great prior entries did well (spiderman, guardians, black panther, and Thor Ragnarok had been a hit and Watiti was doing L&T).
Stuff with lesser known or less popularly loved characters did a lot worse. The box office stuff doesn't all go to Disney, the theaters get returns. For Shang-Chi for example, Disney was probably going to get $200-220 million after the theater cut, but then they probably had spent more in advertising so were still at a loss after the theatrical run but would likely eventually profit off later leverage and indirect revenue from the film.
It was discussed that Quantumania needed $600 million return to break even, but it only made $463 million. Ouch.
Anyway, you can see Disney was throwing money at their MCU films like they could print money, but everything is a decline. L&T is a definitely drop in box office from the prior Ragnarok, even if they did make money on it. Impressively, GOTG3 barely dropped in terms of box office from GOTG2 (they were within about $20-30 million from each other) -- go, James Gunn. And Spiderman is just beloved -- but Disney is mainly getting merchandising income, not box office, because they are Sony films. Durrr....
Pull Spiderman out of there and what do you have left??? Fucking Dr. Strange 2 which might have done well but I consider to be an artistic and writing flop because where can it go next? (1) it abandoned the Mordo setup from DS1 to (2) essentially make Wanda the primary character and ran her into the ground, versus doing anything really that interesting with Strange, (3) really bulloxed its handling of the multiverse, it essentially made the multiverse feeling meaningless rather than cool, (4) introduced a bunch of characters and castings like Krasinski as Mr. Fantastic before 5 minutes later murdering them all in horrific ways, it was a big F-U to the audience. and (5) aside from the introduction of Cleo (who no one really knows, and on whom no info was provided), set up NOTHING else for a next-plotline for Dr. Strange. Like, it was just a strategically bad film... indulgent for Sam Raimi, and otherwise bad narrative positioning.
I mean, the MCU is in pretty shaky territory right now. Disney felt like King of the World through Endgame and then the bottom dropped out. Even Indiana Jones 5 was a box office flop and probably lost them $100 million regardless of whether it was actually good or not (I haven't seen it yet) because making the film was strategically risky with the fanbase.