urhgh
"instead of voting, people..."
NO
there is no downside to trying to improve the world in every way possible
you should still engage in direct action! or any other approach you see fit! but voting might make a nonzero difference, so you shouldn't totally discount it entirely

now I can't say how it is anywhere else, but in the last state elections here, there were a number of seats won by a margin of <100 votes, and the end result was labor forming a minority government.

that's probably more minds than *one* person could change in practice, but a handful of people? plenty doable, and that would result in real policy change in practice.
literally the difference between what we got, or a labor majority government or stronger greens and independent representation