Whoever was left mining after that wouldn't get more block rewards unless it was something more extreme like bricking 70% of miners instead of just disabling th

Whoever was left mining after that wouldn't get more block rewards unless it was something more extreme like bricking 70% of miners instead of just disabling them for a short amount of time. They would be able to mine 100% of blocks but there would be a lot more time between blocks until the next difficulty change. Unless it's something that would permanently break miners it wouldn't last long enough to earn the attackers anything extra in terms of extra blocks mined but facing congestion all blocks would be filled with extra high fee transactions so there would be some BTC to gain, but not from the normal block reward.