Spock once mentioned that his father's race was spared the dubious benefits of alcohol. Him getting drunk off bloodwine with a bunch of Klingons shows why he's chosen to avoid it.
Surprised by the relatively early reappearance of Klingon forehead ridges, or the return to more "normal" Klingons after Discovery? Well, thanks to the Klingon Augment mini-arc in S4 of Enterprise ("Affliction" and "Divergence"), we know that the Klingon physician from those episodes was looking into "cranial reconstruction" surgery to fix that genetic mod. Plus, when he said that "millions" would be affected by the Augment virus dissolving their ridges, and presumably a large Klingon Empire would have a population numbering in the billions, maybe the smooth-headed Klingons just weren't that well-represented in the larger population, and coincidence or other factors made them disproportionately represented onscreen in TOS. Indeed, the dramatic "BDSM" look of T'Kuvma and similar Klingons in Discovery could be an extreme version of plastic surgery to compensate for being smooth-headed at birth.
