So, I buy approximately 3,058 BTC for $50,000 BTC.
Then I give it to you as collateral and you loan me $50,000.
If the price of BTC goes up, I can pay you back the $50,000 plus interest, get my 3,058 BTC back, and sell them at a profit (your profit is limited to the negotiated interest rate).
If the price of BTC goes down, I can default on the loan, and keep the $50,000, losing nothing (you take all the risk of a fall in BTC prices).
Looks like a guaranteed income for me, and a reduced income for you.
You'd have ended up better off if you had just bought the $50,000 worth of BTC.
In that case you'd have the exact same downside risk, but you come out ahead if the price rises.
When something seems to be to good to be true, it almost always is. I suppose this might not be a scam, but financially the math doesn't work out. You either haven't thought this through and are putting yourself in a position to be scammed, or you are attempting a scam yourself.
This is why points need to be offered on the loan (such as 5% or whatever). Payment is up front. So if someone wants a $1,000 loan they will receive $950 (5% of $1000) and hand over the bitcoins as collateral, but required to pay back $1000 + the interest. The bitcoins would have to appreciate at a higher percentage point than the initial points to come out ahead, meaning they need to hold the loan for a longer period of time. The initial points paid on the loan would act as a hedge for the creditor in case of price depreciation and the debtor decides to default on the loan instead of paying the amount due.