I've been telling the same a few pages back
The economic majority is not something ephemeral or abstract, it is a real force which basically comes down to what ordinary users are going to choose. But since they most likely ain't going to delve into gory details of the debates and clashes between miners and developers, they will just delegate their voice to someone or rather something which they trust by default, i.e. exchanges. Indeed, there are quite a few people who just hold their bitcoins in their personal wallets, but since their bitcoins don't move, they cannot be considered as economic agents at all, let alone the "economic majority" even if their numbers are high (which is not very likely anyway)
This even makes retrospective sense when you look at how successful altcoins tend to be the ones you can easily trade and exchange. It's not a coincidence one of the first things a new coin or token seeks is listing on as many exchanges as possible. And with most local crypto exchanges still dealing *only* in Bitcoin, with possibly not enough information or incentive to care about anything else, there's really one logical outcome as to which they'll choose to remain with.