To go further, its crazy how much cognitive dissonance can penetrate even the smartest among us.. If you had some understanding of how modern systems at twitters scale works, you'd know such a bug is highly unlikely.

You have multiple clients (android, ios, web) and a whole cluster of microservices calling each other. The microservices calling each other will easily use up more requests.

IMO the likely culprit is rate limits being triggered by a huge increase in scraping caused by the new api pricing.