Edit: Not a fanboy defensiveness or anything. Just rare to see the contrarian opinion on this, and genuinely curious. Other than the trash combat, I really enjoyed my time with PST.
That said, I would nudge Pillars of Eternity and Pathfinder: Kingmaker above PST as they have an equally good amount of story, NPC interaction, they balance combat better. Pillars II, Wrath of the Righteous and Tides of Numenera, otoh, are below the PST bar in my opinion but ymmv depending on tastes. On the Divinity side, DOS:2 is also a good competitor in the list, although I find it the story tends to be too diluted by combat.
Notably many of the titles I listed above have had Avellone involved at some point (I think he had been involved with Numenera, DOS:2, Pillars I and Kingmaker, maybe more).
I was very skeptical about BG3, especially because even if I listed DOS:2 above, I didn't really like it too much, I'm no Larian fan. But I played the early access and it seems to be golden good so far.
Otoh I replayed (for the billionth time?) all IE games recently and while I still consider PST to be the best IE game ever (only BG2 comes close) it's definitely not uniform. The plot weakens after leaving Sigil, and so do side quests and non-linearity (it's actually pretty linear overall, but after Sigil it doesn't even maintain the illusion). Even the interactions with NPCs are sometimes lackluster (e.g. I would have "pushed" Morte more on the "don't trust the skull" bit) I felt (but it's personal opinion I'd say) that many interactions in PoE went deeper than that.
Anyway, these are opinions and I know of at least one PST fan who would trash the PoEs, Numenera and the Pathfinders (but loved DOS:2), so YMMV.
I haven't tried Pathfinder: Kingmaker, because it has an enormous number of very negative reviews, so I'm surprised you'd put it in the same league as PS:T.
Interesting.. I consider this one of the best albums of all time, unrelated to the "standards of the time" or whatever.
I also don't think I've played a CRPG I enjoyed as much as Planescape. Some of the fallout games may have been pretty close, though I never finished any of them
But it's still worth playing, it is still better than the median cRPG almost 25 years later, and it remains a milestone in cRPGs history: i.e. just like Sgt Peppers or Dark Side of the Moon are still worth listening today.