What's to misunderstand? A miner operating by the old rules sees a segwit transaction as an anyonecanspend transaction. Accordingly, that miner can spend the output to himself, should he be successful in mining the block. Of course, he would still need to get the other miners to extend his chain. But with enough value caught up in active transactions, there is an incentive for the miners to collude thusly. It may not come to pass, but it may. With Core adamant that they always act to vilify and marginalize the mining community, is it really that farfetched that such may come to pass?
6 “Will not all of them taunt him with ridicule and scorn, saying, “ ‘Woe to him who piles up stolen goods and makes himself wealthy by extortion! How long must this go on?’ 7 Will not your creditors suddenly arise? Will they not wake up and make you tremble? Then you will become their prey. 8 Because you have plundered many nations, the peoples who are left will plunder you. For you have shed human blood; you have destroyed lands and cities and everyone in them.