"Full BTC refunds" means a full refund of the price (which is always denominated in USD) via the exchange medium of BTC.
Nope. Read carefully.
The answer is if you buy Baby Jet for 51 BitCoins today and it does not ship, you will be refunded the 51 BitCoins you paid.
Listen carefully because repeating this is tiresome:
A statement based on and made during a long period of BTC/USD stability cannnot reasonably expected to be maintained given a huge, unexpected spike in the exchange rate.
Are you familiar with the concept of 'reducio ad absurdum?"
It means that if your argument leads to an absurd conclusion, it is false.
IE: If BTC went to a million, your assumptions would lead to the absurd conclusion that HashFast owes gmaxwell $98,000,000.
Nothing in the ToS indicates HashFast has unlimited liability for BTC/USD exchange rate fluctuations.
No court or arbitrator will ignore the principle of equity in favor of construing the ToS to require infinite risk for HashFast.
Only the self-interested intentional delusions of the greedy, windfall-seeking plaintiffs would make such a ridiculous case.