I suppose that depends on what you consider “good” for Mastodon. I wouldn’t consider growth simply for the sake of growth to be a good thing. That’s stage 1 of enshittification. It also means a shitload of awful people joining, tons of mod work, etc.
Don’t get me wrong, I’m all for Mastodon and the fediverse becoming more accessible. I just think the growth needs to be for the right reasons.