Dealer hedging moves price when the flow it generates is meaningful against what the underlying market trades. That is a ratio, and the headline open interest figure is only its numerator.
The equity index comparison
Index options carry enormous open interest against an underlying whose tradeable float, for hedging purposes, is finite. Which is why gamma is a first-order intraday force in SPY: dealer hedging is genuinely large relative to what the market absorbs, and the effect is visible session to session.
Crypto options open interest is large in dollar terms and small against a spot and perpetual market that trades continuously, globally, at high turnover. The same absolute gamma is diluted by a much bigger denominator.
What follows
Gamma effects in crypto are real and weaker. Pinning near a large strike happens, and it is more easily overwhelmed by ordinary flow than the equivalent structure in an index. A gamma level in crypto deserves to be held more loosely than a gamma level on SPY, and stating that plainly is more useful than implying the two are equivalent.
It is also why the daily expiry matters less per event than its frequency suggests: each one is small against the market it is trying to pin.
Where the ratio is better
Two places. Around the large Friday and month-end expiries, when a much bigger share of open interest concentrates into one event. And at weekends, when the denominator shrinks because participation falls while the book stays open.
Both are the same insight from opposite directions: what changes is the relationship between the hedging flow and the liquidity available to absorb it.
The honest framing
Read crypto gamma as a description of tendency rather than of control. It says which way dealer hedging leans and where it concentrates. It does not say dealers can hold a level against a market that has decided otherwise — a claim that is overstated even in equities and considerably more so here.