I can only suggest that you must have visited quite a limited selection! There have been a number of different "house styles" over the years from mahogany and dark blue in the 1990s to light wood and pastel colours a few years later. Some have heavy wooden furniture, other light metal frame items. Seating varies between booths, low tables, and high tables with stools. And of course, famously each pub has its own bespoke carpet design.
The ones I visit keep any screens either very low-key or off, so they certainly aren't intrusive other than occasionally during big sports events. That and the absence of piped or jukebox music is a big plus for me.
I must say that those I visit* appear much the same inside, even if the buildings they wre in are very different.
*to deposit liquid, rather than withdraw.