At the end of the day, he needed absolute control over the development and I don't think he'd ever get that over at Litecoin.
It does however align with his 'increase the blocksize' ideology considering that Charlie Lee once pointed out that increasing the blocksize isn't much of a problem at all when it comes to decentralization.
But yeah, I'm sure that even if Litecoin would upgrade its blocksize, it wouldn't ever be enough to please Roger. He's like a child that wants everything to happen right now instead of tomorrow and gets emotional and mad over it.
Litecoin doesn't fit in his portfolio as early Bitcoin investor. He owns plenty of insanely powerful Bitcoin domains and social media pages, which Litecoin can't ever match. On top of that, the brand awareness that Bitcoin provides, and the controversy, is a very important marketing tool he loves to exploit, hence his continuous hostile attitude towards Bitcoin.
That makes sense. Overall, his share in so many early Bitcoin startups and his hunger for blockspace make him so difficult to deal with, that we have to be glad that he forked off back in 2017.
I watched a few of his 2012/2013 speeches and it's a shame he turned into a complete lunatic and a scammer.