you cannot agree or disagree with math, it is what it is At 50% the miner can produce blocks as fast as honest miners and could have an equal length fork Any more and they can produce blocks faster than the network, so for example if the network produced 100 blocks, they could do 110. And they could start 10 blocks early, so their chain would still be the tip, same height, but they now undid 10 blocks

they can't produce an alternate longer chain that's accepted by consensus rules. all they can do is reorganize recent blocks, the further back they want to go, the more hash power they need to have. because honest miners are still adding to the honest chain they need enough hash to not only hash the next block but all the blocks theyre trying to reort. if an Adversary want to do a 10 block reorg I think they need like 80% of the hash to have reasonable chance of success. the numbers are online somewhere.