All Dice/EA have or had to do is decouple the progression in Portal modes from main PVP game modes and likely resolve a lot of the anger around this. They should have known original plan would be exploited as they went through similar with BF2042 Portal and planned accordingly. Despite that, if they had come out and instead of nuking stuff and announced XP/Progression was being disabled until they could code in the split progression I think many in the player base would have been OK with that.
The timing on all of this also completely stinks - Dice/EA should have predicted that the way they implemented Portal was going to allow for bot farms. I say the timing of all of this stinks because the only people I heard or saw talking about bot farming were those same streamers Dice/EA are catering to. It was allowed to stay juuuuust long enough for the streamers to get all their unlocks before Dice/EA not only dial progression back, but completely remove ability to get XP at all when bots outnumber human players? Yeah, nothing fishy there at all.