I'm not certain, but the existing manufacturers haven't yet figured out the best way to make their composite rods more "grippy". Seems like you can get them with a spiral groove or with a spiral ridge. So they haven't been around long enough for one form to win out over another.

Basalt fiber was also classified as a Soviet military secret for a while, so I'm thinking that applications useful for civilians, like concrete rebar, have probably been around since the 1990s.