I do not think its a good idea to go back to the old square tapered BB.

These square taper are heavier and causes many problems like noise.

Moreover, many brands do not respect the JIS or ISO standards (ther are two official standrs for square taper) and mounting a square taper crankset from one brand on a square taper BB from another brand even if both are JIS or ISO often causes problems, the BB square going too far or not far enough in the square hole of the crankset.

The Birdy BB is a standard one, you can mount any standard BB in it, no need to use a Ridea BB on the Birdy.

There are excellent modern crankset from the main brands Shimano, Campagnolo (look ate the gorgeous Super Record carbon/titanium, its easy to find the old 5 arm model), SRAM. And also smaller brands like FSA.

The price/quality ratio of these crankset made/sold in much bigger quantities than the Ridea is much better.

My Birdy Titanium was factory equipped with a FSA SL-K Light carbon crankset with external bearings which is lightweight and fits perfectly in the Birdy.