This is a good point, but PAs can be directional and beamy too. I got tinnitus at a gig where the PA was too loud and aimed right at me. And I’ve been at many gigs where even the back of the room was finding things painfully loud.12 pages I haven't read every post. But what I haven't read is a single reference to the listening audience. For myself, a data point of one, I have no interest in being on the victim end of 85w-100w 2x12 or 4x12 which is producing the sweet tone of power tube overdrive. If you've never ventured from the stage, amps are very directional, even a 4x12. The poor 1/4 of the room in the crosshairs has a completely different experience then the rest of the room and the band on stage.
A well run PA not only provides the volume, but maybe more importantly provides a balanced sound for the audience. My preference in the crowd would be lower volume amp through a high powered PA.
At some point, volume is volume and it ceases to be enjoyable for most people. Playing excessively loud is narcissistic and disrespectful to an audience, especially in a small room or bar.