You won't find them at dealers very often (they're not popular) but they are available for most of the budget lines provided by the manufacturers.
Feel free to look for yourself. They list it under "powertrain" in the specs pages.
> is different from “broadly available”,
FWIW, my definition boils down to: available from most manufacturers, in the major form factors (truck, SUV, sedan, compact, sport).
No Chevy, Dodge, GMC, Ford. That's just one huge gap.
Update: also, if you extend that to SUVs, one of the hottest markets, I think the only model you add is the Ford Bronco.
So there are no entry-level pickups or SUVs as manuals. For CUVs you could probably add Kia Soul and Mazda, but not much else.
Most of those are performance oriented. Those that aren't will probably be all automatics.
Miata, Wrangler, Mustang, and a handful of others, but they’re the exception rather than the rule.