If you were to protest Piggly-Wiggly grocery store, you would do so by not going there and not by tampering their products or blocking people from entering the store.

In point of fact, preventing people from entering a facility is how picketing works.

And your second argument can be turned around to the actual reddit protest itself, like you said reddit is not important so it is equally unimportant, technically speaking, what they are charging for their API.

They are making moderation more expensive and more difficult. This is a labor issue. The fact that the workers are unpaid doesn’t change that. The bosses screwing over workers is not unimportant.

Same thing as if a movie theater were engaging in wage theft against their employees: wage theft is important, but you seeing a movie at that particular theater isn’t.