That’s another thing that has always frustrated me about COD since MW (2019) is how slow the BP goes. I played a lot in 2020 and 2021 never maxed out the BP once.
As for DMZ they’ve made changes for the better from what I’ve played in the last month or so. Was surprised to hear a recent podcast say DMZ is the best mode now in COD over WZ.
Someone did the math and to finish the BP in a season, you need to play well over an hour per day to get through it.
I wouldn't even want to play that much COD, even if I could.
The BP seems mostly time based too. It doesn't really seem to care about XP. I can go nuts in one game and bad in another, and it just gives you a sliver of progress either way.
The only way to do it, is to go absolutely nuts when they have double BP xp, which is usually only one weekend a season now.