In this home office setup, I’ve come to really appreciate 2 pairs of fairly large, sealed 2-way speakers. Both are relatively inefficient, as most sealed/acoustic suspension speakers are. So on the rare occasions when I really crank the system, having lots of watts matters. There’s definitely a benefit to big, strong amps that loaf along at <10%-15% capacity even at peak volumes (ie, if good sound = a good power supply, it’s an unstressed, high-capacity PS that one is hearing).
But at other times when lots of watts aren’t needed, it’s down to how well designed and voiced the amp is; how carefully the components were selected for sonic as well as electronic properties; how robust the PS is; the quality of circuit layout and wiring...all the audio verities. Spending lots of money on an amp isn’t a guarantee of good sound, but I suspect really good sound becomes more commonplace with the bigger, heavier, more expensive amp designs.