What is the point of taking out a loan and using my Bitcoin as collateral when I can simply sell a small portion if I urgently need money? If Bitcoin is the only asset I have available, I would rather sell just enough to take care of my needs and buy back later when I'm financially stable again.
The point is that your Bitcoin can continue to appreciate while the loan runs. And the fact that the long term trend still appreciates, can make this an attractive option if you design the contract in a way where you wouldn't be forced to liquidate in the case of a dip. This would mean to overcollateralize it a lot.
If I understand it correctly the "deal" basically boils down to: it is a profit for you if your Bitcoins appreciate more in the time period than the interest rate you would have had to pay in the same time period.
It doesn't even have to appreciate exactly in that time period. For example: Bitcoin is at 80,000 and your loan's deadline is 2 years, and in these 2 years Bitcoin declines to 70,000 just because you catched a bear cycle - only then to appreciate again and go to 100,000. In this case you still have profited.
This also means that the kind of contract is most attractive as long as Bitcoin appreciates more than a common interest rate. It is still interesting if the expected Bitcoin appreciation allows you to significantly lower the "effective" interest rate (e.g. if you need the liquidity to start a business). But of course the contract is quite risky.
I also have some problems with that kind of contract because you give up self-custody, but people who already are storing their Bitcoins at exchanges and ignore NYKNYC should have no problem with such a contract.