But see we were talking about a X-Men tv series that visually look on par with the Mcu movies. In my preference, the Avengers. Yes story matters. But remember X-Men are superpowered people and with the right amount of budget, there's a lot to be done.
There aren't a lot you can do with 11 million per episode. I watched the Boys and it always make me wonder why some of the Seven are rarely part of the action. Electricity, throwing people in the air, glowing eyes, these are basic vfx/stunt work that aren't hard to pull off. But action scenes that require several days to finish? Can they do a highway chase scene without looking dodgy (Hawkeye the show). What about the Sentinels, can they be featured in every episode?
They wouldn't do able to do all of those for every single. Even if its just 6 to 10 episodes. They most likely save the big pieces for the premiere or the big finale - which feels quite limiting.
If you think $400 million is beyond incase, then just look at what Marvel Studios have accomplished with $200 million plus budget for She Hulk ($225m) and Secret Invasion ($212m)... the action/production values in those shows aren't even close to a highly well made MCU movie. If you think they can off X-Men tv show under a "TV budget", I highly doubt they could. If the mutants are just gonna sit there in their classrooms with their casual clothes on and talk for ten minutes straight okay, maybe they don't need a large budget.