This isn’t a problem in the game. The problem is the addons arent baseline for the game. When theres 15 different things going on in a game, it isnt exactly as simple as you think to track things in your head.
Nobody is forcing you to use any addons if you can manage well without them. At least 70% of people who use most of those addons don’t even look at them and end up clouding their UI.
If you are interested in getting the good stuff for PVP, check this post https://eu.forums.blizzard.com/en/wow/t/5-minute-read-to-improve-in-every-arena-bracket/435403