Avengers: Infinity War, Thor fell into depression. In the five years between then and the main story of Endgame, he had gained a lot of weight spending his time just hanging out with Korg and Miek, playing video games and drinking copious amounts of beer.
keeping Thor fat in Thor: Love and Thunder, Marvel has the opportunity to explore more of his character.
There were good aspects of “Fat Thor”, and committing to a big change like that lets them get him right. Marvel often doesn't fully commit to character changes in the Marvel Cinematic Universe. Tony Stark blows up all his Iron Man suits in Thor got a cybernetic one early in Infinity War. Letting Thor remain fat would show they’re willing to make a change like that a longer story point. After so many character changes that are brought up in one movie and hand-waved away in the next, that would be a welcome change of approach.
The main benefit of keeping Fat Thor is letting them address the issues that came up in Endgame while keeping what worked. Thor being overweight isn’t just a joke, but a look at how depression affects different people. Thor failed to save the universe by not going for Thanos’ head. This caused him to fall so far into depression that he couldn’t do much more than drink, overeat, and play Fortnite with Korg and Miek. It’s a jarring transition, and while it's blown up to superheroic proportions in Endgame, it's a real issue the movie would be enriched by exploring more thoroughly.
Thor: Love and Thunder can fix the Tony Stark calling Thor “Lebowski”.
It’s a difficult balance to strike, but if anyone can manage that, it would be Thor: Love and Thunder director Taika Waititi. He made Thor: Ragnarok a star vehicle for how funny Chris Hemsworth is, while still telling a serious story about the effects of colonialism. This could be the next topic he tackles with the sequel.
