As a person who preferred the Premium pass, (mainly to have a more regular content flow without getting drip fed) I have to admit you're a little misguided on this one:
"No split player base. Everyone had access to the same maps and modes. That kept the community together, instead of fragmenting it based on who bought what."
Having the seasons/battlepass (as much as I truly do not like them/their idea) they never locked a weapon or map out for not paying for the premium battle pass (as they were all in the baseline upgrade path), or I believe the weapons became available after the season via normal unlock means (I honestly don't know as I always had everything unlocked by the end of each season). Skins ,obviously, are a different story, but those don't affect gameplay like maps/modes/weapons.
The biggest issue with premium is that it _did_ split the playerbase based on who paid for premium and who didn't (or who bought individual DLCs and not others). It also locked weapons and maps behind those particular DLCs and such, so it caused quite a bit of consternation for server hosts that largely ended up running the baseline maps because otherwise they'd cut down their player counts when maps changed (if it allowed the player to join the server at all if they weren't entitled to the full map rotation).