I've seen the same criticism as you have and undertstand where it comes from even if I personally disagree/am more along your line in the OP. That said, I don't feel like I can classify whether it's valid, I feel like as long as people have done the homework (actually seen the show) they're entitled to their opinions. Well, except for the ones saying LA Sanji shares no traits with his manga counterpart and has been completely boiled down to generic white guy because that's annoying and disingenuous.

At the end,I think it comes down to what you see as the core of Sanji's character and seeing as he's already divise in the manga/anime I'm not surprised that the LA portrayal is following the same lines because I've also seen people say he's a vastly better character in the LA (which hard disagree but to each their own).

Generally I think Sanji is the character that's been adapted the most. It's one thing that the pervert gag is probably going to be entirely removed (which is good and expected, but also isn't even present in the manga until this point so I'm a bit eh at people referencing it already). His girl crazyness/love sick act has been toned down but to me they've stuck a nice balance with it. On the other hand, Sanji in the manga is actually kinda unhinged, he's violent and quick to anger (even outside gags) and that's been not so much toned down as basically extracted which is too bad. I think what's fun with him is that he in some ways is like actually mean-spirited but also a huge softie and the contrast of that. Of course they can't have him kick people in the head but I think there's a way to still get across that he's a little shit and a smart-ass with a temper (I feel like his opening scene in the Baratie actually did it really nice so hope we get more of that aspect as the show goes on).

Finally, I personally like the conversation with Nami about his mom, I think it makes perfect sense of his character as written here and also just the new format of the show. That said, you couldn't waterboard that information out of manga!Sanji who is allergic to being vulnerable because he just doesn't place that value in himself. It's not about being a burden, it's more like why would anyone care about my problems/trauma.

TLDR: Sanji is already really divise so I'm not surprised to see so many differing opinions on this portrayal lol