It's conceivable that some spot exchanges are or were still from 2017 to now, either malicious and/or incompetent, which would facilitate the continuation of such behavior, likely by more players than one or two.
"The spot market is so thin" I also think is incorrect. GDAX is normally 0.01 USD wide (albeit for small amounts) and often-times under $1 wide for many BTC. I would call the spot market very thick, if anything. You can get off what appears to be very large amounts of BTC with minimal slippage most times of the day.
"didn't seem to take much open interest in the futs to whip the underlying" -- are you saying a futures move would lead the market? I respectfully disagree. All the entities I know price futs from spot and are generally putting on the arb in this order, not the other way around.
Sounds reasonable, thanks for clarifying and correcting.
I wrote a script[1] that pulls down the public order books for Bitstamp, GDAX and Bitfinex, because I was interested in seeing the depth of the BTCUSD market, and right now you can offload:
258, 301 and 325 BTC on GDAX, Bitfinex and Bitstamp, respectively (total: 884 BTC), at 1% slippage for 3,544,921, 4,152,783 and 4,452,134 USD, respectively (total: $12.1m).
Of course if you want to move larger amounts there are specialized OTC markets that handle large block trades, e.g. Cumberland Mining. Of course the lit exchanges are important for price discovery.
It would be interesting to compare the BTC market depth as a percentage of market value to other exchange traded assets.
It makes sense the price has stabilized recently due to how strong the recent bull market was, it will likely need some time to relax and consolidate before it decides what direction to push next.
also, I surmise that a major factor in the correction we've witnessed in the past month or so has been the congested mempool (high fees and slow tx times).