The RX1 list price is about 3000$. This was the price for the original RX1 and is also the price for the new version. How much do you expect a hypothetical medium format version to cost?
Assuming that price is a linear function of sensor area (within the RX series):
rx100m4 = [948, 13.2*8.8];
rx1rm2 = [3300, 35.8*23.9];
p = polyfit([rx100m4(2) rx1rm2(2)], [rx100m4(1) rx1rm2(1)], 1);
mf_area = 43.8*32.8;
rx01 = [polyval(p, mf_area), mf_area];
What kind of lens would make sense in such a camera? Street photography? Landscape? I think that it would have some great aspects. Too bad that it would be made by Sony.