SegWit was activated by consensus. That's all that matters. If consensus hadn't been reached, SegWit wouldn't exist in Bitcoin. Users, miners and non-mining nodes could have continued persuing a minority chain with SegWit in the event it hadn't gained consensus, leading to two chains, the minority chain being an altcoin. The same applies to the 2mb blocksize. There will either be consensus or there won't. If there isn't consensus for 2x, again people can pursue a minority chain as an altcoin. The thing you seem to be failing to grasp, which I doubt will change any time soon, is that like SegWit, there may be consensus for 2mb and that will then become part of Bitcoin. If that happens, you can still follow the altcoin if you don't like 2x, simple as that.
This is practically true, but I presume what he was referring to was that Segwit wasn't a hard fork like S2X. As I understand, there was never a hard fork on Bitcoin to this date and many things was left (like OP codes) with the intention to be implemented as a soft fork in the future. However, Sathoshi did seem to want to make a hard fork to increase the block size in the future.