TradFi Markets:
CME futures showed a slightly diminished amount of activity after the spot BTC ETF approval. Open interest trended down from the peak of ~$6B to ~$4B, representing a nearly 33% decrease, with volume dropping off after the ETF mania. However, open interest still remains significantly higher than what it was for most of 2023.

Source: Velo Data
On the other hand, CME options open interest remains fairly stagnant, and compared to 2023 levels, has not seen significant growth. Much of the run up in options activity towards the end of 2023 can likely be attributed to speculation around the spot BTC ETF approval, with activity seeing a sharp drop off.

Source: Velo Data
CEX Activity:
Looking at BTC markets on various CEXs, volume was elevated before, and during the spot BTC ETF approval, while open interest remained fairly stagnant with no significant change from previous months. However, post ETF approval, volumes have not seen notable growth, which is reasonable considering one would only expect elevated amounts of market activity in the TradFi markets, specifically the various approved and live ETFs.
Ren leads coverage on Options, Structured Products, Money Markets, and AMMs. Previously worked at a crypto hedge fund managing DeFi strategies.