not really, even if you put a tonally balanced speaker in a shit room (baren concrete walls) it will still sound bad even with modal region dealt with. However put a mediocre speaker in a great room and you would have an amazing experience nonetheless.
How come you think speakers that measure like crap sell like hot cakes in show rooms?
That's an unrealistic objection.
Take one of the speakers that have good, consistent radiation patterns that are held in good regard here—they will have more freedom of placement and listening position in any domestic room. No issue sitting above, below, to the side. Take a mediocre speaker, which would be any with typical cancellations off axis and some beaming, plus some FR inconsistency, maybe a little port resonance. With one of those you'll hear more differences as you move around, depending on where you sit, etc. Even in PA circumstances and parties that can be anywhere (I've been to plenty of warehouse parties), good speakers are easier to set up. "Tonal balance" is underselling the role of FR.
Room acoustics is less of an issue than isolation. High in-room noise floor is the killer of good sound. If you have some way of applying EQ, life is considerably easier. But there's only so much you can do about traffic, plumbing, washer/dryer/dishwasher/HVAC, nearby family arguments, without spending a lot of money rebuilding or renovating.
There are definite circumstances where room acoustics is a significant factor. Cramped spaces where the system is up against one wall or your head is right up against the back wall, or you're in a large room with strong late reflections, or an open concept room with unusual layout, maybe a few pillars and inconvenient dividing walls. Or a room that's mostly windows. Even under those circumstances, good speakers will simplify the planning. Treatment will help, of course, but it's not a dominant factor.
This is even after significantly investing in treatment myself (8" porous and panel absorbers) and experiencing the benefits.
I can't comment on show rooms because I don't like listening under those circumstances. I wasn't introduced to good sound that way, and I go only because it's fun to find new gear and talk.
Edit: The single best thing I've ever done to treat a room is applying rubber weatherproofing to the edges of a door. $40 for good, compressible, springy stuff with adhesive backing. I live in an open concept condo now, which limits me severely, but in my old place it dropped the noise floor massively in the midrange and highs. I went from being able to hear conversations to hearing the occasional mumble. No kitchen noise, no TV dialogue, nothing. I was of course lucky because of the layout of my house, so this isn't something to I'd expect to work that well every time.
Blocking noise with passive barriers is cheap and effective if you can do it. One of main tools of the trade in pro acoustics.