It's the opposite, FTX was selling customer BTC to prop up their own coins. This is also a clear example of how difficult it is to prop up a coin, even relativ

It's the opposite, FTX was selling customer BTC to prop up their own coins. This is also a clear example of how difficult it is to prop up a coin, even relatively illiquid ones like the FTX coins. FTX could sort of prop up their own coins, but not really. They couldn't move prices high enough to keep lenders from recalling capital, and they couldn't support prices at all when there was a confidence crisis before the collapse.