I liked MASH. It handled progressive/liberal themes better than a lot of contemporary media. Pretty overtly anti-war and pro-humans getting along, I can't really fault it for that. Not to be apologetic about it, but it probably went about as far as it could for a show made at the time. Even with the whole Klinger dressing like a woman to get out of the army thing, he never actually convinces anyone that he's crazy, or even that dressing like a woman is that big a deal, and there was even an episode where a Swedish doctor mentions to him that they've been doing gender reassignment surgery in Sweden if he wanted to look into it.
The anti-communism and colonialism are there, for sure. More obvious as a lack of self-awareness about them than in any overt way. I'm sure the writers thought they were being pretty edgy and enlightened, even while not really being that critical of their own deeper biases.
It's sort of hard to analyze a show made in the 70s that was set in the 50s. For example, it's not clear how much of the misogyny was from the fact that it was a somewhat exaggerated depiction of the 1950s (in the military, no less) vs how much of it was just baseline 1970s misogyny. In absolute terms it's very standard lib media, but made well before that was the norm. This was when you could say the n-word on TV but you couldn't say "pregnant". You can analyze all the problematic stuff, but at some point you're just criticizing 20th century American culture broadly and not really making a point about the show itself in context of that. Not that 20th century American culture is worth defending, just that there's not much to pick at that's specific to this show. America in the 70s was racist and misogynist, news at 11.
Star Trek is still the GOAT of being ahead of its time and actually influenced by leftism as opposed to left-liberalism, but MASH was alright compared to a lot of stuff that came before it, and plenty that came after it. Watching it without a laugh track would probably improve the experience.