Earlier quoted context omitted.
Segwit2x was an initiative to replace bitcoind with btc1. It is strange to describe it as being rejected by bitcoind. Bitpay's business model was always a bit of a special case. Undercut centralized services on fees? Not likely. It'll work as long as there are early adopters to spend their windfall, but in the long run they'll need to pivot. And not to the next altcoin.
Segwit2x was an initiative to increase the block size. It only required replacing Bitcoin Core because Bitcoin Core refused to merge a block size increase. If they had agreed to merge a block size increase, then btc1 would not have been necessary.
The Bitcoin developers (not "Bitcoin Core") had just implemented a block size increase after years of discussion.
The segwit2x intiative didn't take part in this. They didn't bother even writing a specification, let alone a proposal or take it through public discussion.