On one hand you have politicians whose job is to implement policy, on the other you have people who have to go out of their way to protest.

In the end politicians win, simply because regular people have other jobs.

You get initial push from protests, but in the end time works against them.

So no, protest are not the solution, just a delay.

and yet there are countless examples of the causes of protestors winning long-term victories

usually the people who choose not to protest for/against issues they care about do so for fear of police, fear of embarrassment, and/or laziness, not because they don't believe the countless sociological studies which have shown protest to be an effective form of political action