Twitch has employed new bot-detection algorithms which have taken a hatchet to botted viewers.
One stream ran recycled content consistently at 2k viewers for nearly 3 years straight to farm botted adrev, which was slashed to 250 viewers after the change. Several very large creators saw their numbers slashed completely. Asmongold lost ~20k viewers. Lacy lost nearly 3/4 of his viewers, being cut from 30k-40k down to 8k-10k.
It's likely not all the bots have been removed, Twitch is calling this their "first pass".
Twitch's ccv is likely more accurate than Youtube's right now.