The curves of the letters are not smooth.
Converted to curves:
When exporting to jpeg, tiff, etc., this problem is quite unpleasant.
Quite possible that it's a poor imitation of the real "paid for" font. I call it a "prated" font. Seen it many times.Quite easy to autotrace images of characters and save as a font. But no one takes the time to "clean up" the autotrace before saving out.
Don't believe this is the case here. Has to be an anti aliasing issue.