We have to do it. Some of us have to do it in different ways. Doing small things where you can is all well and good but literally none of us are making a single impact in capitalism by making different choices about how we're forced to participate in it. Focus on tearing it down together rather than picking apart individual choices because those individual choices still result in participating in capitalism.
Equating human cruelty with animal cruelty is good because they're similar in many ways, including the reluctance of liberals to speak up or take any inconvenience in their lives to end it.
I think vegans should stay in their lane and stop trying to equate simply not being vegan with slavery and ethnic cleansing.
But it's also a false equivalence because slave owners own the means of production under slavery, whereas non-vegans do not own the means of producing meat.