I just built this on breadboard and it sounds nice! It really beefs up a sine wave and it sounds like it’s folding the triangle…nice, whatever it is!
If you like that sound, check the near-infinite amount of schematics of guitar distortion pedals. Like 90% of guitar distortion and overdrive pedals are are based on that kind of diode clipping and/or having diodes in feedback-loop of non-inverting op-amp configuration.
…and then there’s the HM-2 which has diodes also on the signal path to clip wave around zero.