I get that, but I don't feel good about that solution. You're sort of beholden to that specific client.
Given new lemmy is as a platform, I don't want to feel locked in yet (though I understand instance block lists might be cross compatible between all client apps supporting the feature).
Another counter argument is that an instance block list should be relatively short. Keeping this list in a separate location and manually re-applying will probably not take up a lot of time.