Why is this not implemented?

Aren't the ones on the right just regular flat curves that is put on a 3/4" riser block and not 'sloped'?

That is the point. The question is why is it not as 1 piece. If you take a look at where the male and female connectors are, you can see that the first sloped one has only female connector on the top and male connector at the bottom. Why TOMY didn't create a sloped curve where the male connector is on top and female connector at the bottom? Also I'm talking about the normal sloped curve, not the vintage type.

This is 2 parts, but 1 whole part of this type does not exist. If you have 1 more yellow pier and 1 more curve, you can see that there is a abrupt break in between the tracks. But if you have a whole slope rail, you can see that the angle straightens just at the edges of the rail. (this stabilises the tower structures)