His big ones are slowly drying up. Swagginz and lordlamb were the most visible recent ones. ttv_noble allegedly is also gone. infinite55 has been notably absent aside from a $25 tip this month. There are still others like PlanetJeff, Rob Warren, flybeast, henk douma, and so on who will show up on occasion.
As for why he's stopped talking about taxes? He got his payment, and he also got two months worth of Twitch income due to the change in payouts they made. So between that, his two begathons, and Mama Burnell's $4k, he's feeling flush. Watch what happens the next few months, though, when he doesn't plan ahead and the lack of whaling starts to take effect. And what's he going to do about 2019's tax payments? He had to get a payment plan for last year--they won't do that a second time.