I just replaced the bra straps on a bra to make it wide on the top of the shoulders, where thin straps can gouge into the shoulders. The wider straps distributes the bust weight load over a wider surface area to ease the pressure, but tapers to the same points of connection as the thinner original straps so the wearer wouldn’t feel like they’re wearing big suspender straps that aren’t exactly feminine. The straps are double layered and serged for strength, turned inside out, but thin enough still that a regular non-white blouse or thicker top should cover it just as well as a regular strap. The taper is also asymmetric so the edge towards the neck runs further off centre, allowing for a slightly longer edge that may be needed for a rising shoulder to neck.
So here’s my question. Why don’t bra makers do this?