https://www.techradar.com/news/why-lg-is-leaving-the-mobile-...
https://www.forbes.com/sites/siladityaray/2021/04/05/after-y...
These two articles indicate only that LG was struggling in the market and decided to focus elsewhere.
I don't know what the poster meant, but drawing a conclusion that there is some correlation due to statement choice is normal.
No, clearly saying that LG tried all the OP was asking, but there wasn't enough of a market for it, so OP is obviously in the non-sufficiently profitable minority.
There might still be market for users looking for modular phones. Fairphone comes to mind in this aspect.
LG failing to provide a product for this specific market niche isn't enough of evidence to support the claim that the market itself doesn't exist, only that LG couldn't or had no interest in maintaining it.
without the proper usb port ("only" type C), LG had a number of phones ticking all those boxes (while being good phones, good cameras, good screens, the whole thing). They sold so poorly LG left the market.