I would certainly miss the unfettered data usage
When I'm out and about with my camera, in Europe, I like to be able to frequently upload photos from my camera to my phone, and then onto Lightroom in the cloud. If I have the big Sony camera with me, that means I'm shunting a lot of data around. Of course, local SIM cards are readily available and I'm perfectly happy to go back to doing things that way.
So, I think the reintroduction of roaming charges (or simply making my data allowance unusable, as I've found Three are quite good at) would disproportionately affect those who don't have the gumption to find cheaper alternatives. In other words, mostly the very people who voted for this.