How best do you recommend continuing the protest? Simply stop using reddit altogether, or is there a malicious compliance you recommend?

Unfortunately, that's probably the only route, IMO

My usage has gone down significantly since the API changes but I haven’t been able to kick it altogether.

While it's not exactly a perfect replacement for reddit yet, lemmy can help with that, i've found. If you click to the "all" feed you can basically get a slows/less populated version of reddit r/all. Really all it lacks at the moment is user participation, which has been climbing a lot over just the past few weeks.