Look at the details of that report. They're measuring by _number_ of tweets rather than impressions. Hate speech impressions are down. i.e. if you want hate speech you have to go out of your way to find it using bots. Normal users are seeing them less after the purchase.

It's really tiring to counter so much misinformation about this that flies about.

It's not just a one-time drop either, the impressions continues to go down. https://twitter.com/TwitterSafety/status/1613335965996810241