The low interest rates are mainly caused due to the platforms only slowly adding new loans. See my post about the latest status of available loans on all three platforms.

P2P Lending PlatformInterest IncomeXIRRTotal InvestmentCurrent Value
Mintos€ 119.97
10.39%€ 11,000.00€ 13,969.77
Twino€ 147.3010.07%€ 15,000.00
€ 17,705.77
Swaper€ 85.4114.45%€ 7,000.00€ 7,177.37