The standard problem with "just voting" to solve problems is that you can only vote for the options you're offered. If all the options on the market suck, voting for the lesser of the available evils will not address the fundamental source of your dissatisfaction, and may help entrench it. If you vote "with dollars" there's the additional problem that dollars are not uniformly distributed, and a few wealthy "voters" can and will disenfranchise everyone else.

Abstaining from buying from companies you disagree with can help, but it is only one part of the broader solution. When there aren't alternatives yet "on the market" you may be forced to hold your nose for a while and buy from the vendors you hate while advocating for change and working toward their replacement. You don't have to solve every problem in your world at once so long as you're building in the right direction.