That comment is more about a theoretical scenario that actually has solid consensus.
The real problem with segwit2x is that the consensus was dropping and was trending toward a very weak level. It had strong consensus for long enough to do a switchover, as far as I understand, but it didn't take the opportunity and then people eventually started to change their minds.
from https://lists.linuxfoundation.org/pipermail/bitcoin-segwit2x... :
"Unfortunately, it is clear that we have not built sufficient consensus for a clean blocksize upgrade at this time."