strangely enough,they haven't been so fussy about Bitcoin Cash fork
It's not strange - the distinction is that NYA's intention is to call the new fork "Bitcoin", and a not-insignificant number of merchants and services are likely to be calling it "Bitcoin" as well. Bitcoin.org only had to distinguish between Bitcoin and the new fork Bitcoin Cash before, but this time they have to distinguish between Bitcoin and Bitcoin, which is significantly harder.
However, their points on the page should be as neutral as possible. When (correctly) pointing out that "miner actions cannot be used as a justification to redefine Bitcoin", they are essentially using a strawman, because BIP 141 itself required 95% consensus from miners, but that doesn't mean that Bitcoin Core think it's the only step to SegWit on the current BTC chain having widespread adoption. Similarly, not all SegWit2x supporters assume that miner actions are the only factor in consensus.
Currently bitcoin.com is going to be referring to SegWit2x as "BTC" it seems, so there may be some conflict between the two sites. Since bitcoin.org is supposed to be an informational site while bitcoin.com is more of a general news site which shows a lot of different information, it's possible that bitcoin.org will stay fairly mellow about their opposition to SegWit2x and Bitcoin.com, while Bitcoin.com's actions are somewhat harder to predict.