I don't personally think the advanced technology itself is the problem, but the way it's represented. Allag and Garlemald with their advanced technology exist, but they're both very far removed from the reality we live. Allag is kinda just straight up advanced fantasy with the way they've generally been presented, at least aesthetically (Late Allagan gear notwithstanding), whereas Garlemald, though advanced, leans into more of a Dieselpunk aesthetic. What both of these have in common is that relative to the society we live in, they're further back in time, with Allag just not really being comparable to any period of history, and Garlemald being an era backwards in time aesthetically, despite how advanced it is.

Solution 9, on the other hand, leans into the aestehtics of cyberpunk, a genre of sci-fi explicitly built around things only present in our current society and onward- it's built upon the technological advents of the information age. I think to me, that's what makes Solution 9 grating whereas Allag and Garlemald are fine, because for how advanced they are, they still feel like they'd exist backwards in time in other aspects, and don't hit too close to home. It's started to feel a bit like that as of Endwalker too.

Personally, I prefer when advanced technology in fantasy can exist without pushing society closer to what our own modern reality is like. Doesn't mean it shouldn't be consequential, but ultimately, what I want out of a fantasy setting is a world that feels different from my own, and this certainly is not helping that.