while generally true in case of borrowing fiat against crypto collateral a trusted (centralized if you will) arbiter is a feature not a bug as the fiat interface is always "centralized"
the ideal solution (simplified) should look like this:
borrower locks collateral to 2of3 multisig (2 parties and 1 arbiter both parties trust - otherwise no deal closed)
lender sends fiat
repayment date and interest are given
1) repaid in time including interest -> arbiter and borrower unlock collateral back to borrower
2) default -> arbiter and lender hand over the collateral to lender
easy as that, no tradfi bulls**t and unwanted complexity like installments, margin calls, topping up collateral, etc.
I must︀ be missing something because it seems there is no such service on the market
the ideal solution (simplified) should look like this:
borrower locks collateral to 2of3 multisig (2 parties and 1 arbiter both parties trust - otherwise no deal closed)
lender sends fiat
repayment date and interest are given
1) repaid in time including interest -> arbiter and borrower unlock collateral back to borrower
2) default -> arbiter and lender hand over the collateral to lender
easy as that, no tradfi bulls**t and unwanted complexity like installments, margin calls, topping up collateral, etc.
I must︀ be missing something because it seems there is no such service on the market