I mostly agree, but it also depends on the size and the shape of the fillet. Large sweeping curves that stay close to horizontal for a long distance are bad, but a tight corner can still look better in G2/G3 than just G1. On the top at least, because fillets on the bottom create sharp overhangs that don't print well.

Also, if you have that option, filler + sanding + paint can hide the layers completely, but preserve the overall shape.