You must be buying lenses made in East Balookistan and sold in WalMart. Every single modern lens I've
purchased in the last thirty years has been superb. Englarging lenses, view camera lenses, MF lenses,
35mm lenses. Never a quality issue. Not once. Of course, I'm going for top brand stuff, Japanese Nikkors and Fujis, Kern optics, German Schneider. Even all my older Apo Nikkors are optically superb.
About the only cheapo enlarging lens I own is an 80/4 El Nikkor - a poor performer with medium format
film, but surprisingly good at the center of the field for 35mm use - significantly better than my old 50mm Componon S.