What if we eliminated interest rates (as technically, they constitute the exploitative practice of usury, and therefore theft), and opt for equity participation

What if we eliminated interest rates (as technically, they constitute the exploitative practice of usury, and therefore theft), and opt for equity participation instead? (This is how Islamic banking operates, as riba is forbidden. Indeed, usury is also condemned by the Church, and Catholic banks would sustain themselves on, e.g., service fees for the labor involved in, say, issuing a loan or investing on someone's behalf or whatever. And the Jewish Talmud forbids taking interest between Jews, though it does permit charging goyim interest. Regardless, you do not need to appeal to religious law or teaching as these merely reflect the demands of justice and just economic exchange.)