I don't know about this place in particular, but I've lived in places that attracted lots of tourists.
Tourism brings a whole bunch of problems, and the more tourists there are, the worse those problems get. The locals often (barely) tolerate tourism because it also bring economic benefits. But if those benefits don't filter down adequately to the locals (at least adequately enough to compensate for the losses), then tourism just becomes something that makes everything worse for them.
Living in a place like that, I've found the locals that complain the most are not coincidentally among the least educated, least intelligent, and most unlikely to recognize the economic benefits that tourism brings to them.
These are people who are employed as servers and similar service workers yet complain many of their customers are from out of the area. I don't know how you fix that. What's crazier is when you point out the economic drain that would occur were tourism to slow, they often simply shrug and point to the state to save them from their woes.
I'm just noting the irony that the activists embrace refugees coming to Venice but not tourists. And really I'm focusing on the way that they say "no one is illegal" when they clearly don't like tourists and want to make them illegal. (And I might agree with both of these stances in a less ironic way.)
Tourism brings a whole bunch of problems, and the more tourists there are, the worse those problems get. The locals often (barely) tolerate tourism because it also bring economic benefits. But if those benefits don't filter down adequately to the locals (at least adequately enough to compensate for the losses), then tourism just becomes something that makes everything worse for them.