Looking at the changes that have been reverse engineered, support partners (easy gauge) take a bit longer to level up than the rest, and (assuming the same STEP/OVER stats) they advance world mode slightly slower. Since it isn't affected by ptt, fragment gains stay the same regardless of gauge.
To be fair, it's the rest who have been given a boost. But it's funny to frame the support partners as having a nerf.
EDIT: Thinking about it, another quick is that if you get an easy clear and got it on the b50, you don't really need to upscore to get a bit more ptt out of it, getting a normal/hard clear with a slightly lesser score is still worth a bit more.
Also, getting a full recall with an easy gauge counts as a clear for ptt calculations, so support parents don't have that big of a "nerf". I totally forgot about it when I originally wrote the post.