Not sure, as I haven't grow Gorilla (Glue) strains before.
Mine are "guerilla" plants, as in, illegal stealthy plants out in the wild, not "Gorilla Glue" strain.
They are sativa dominant strains from La Buena Hierba.
Most pictures and vids I have seen of Gorilla Glue looking fairly big.
Can be a lot of reasons, light intensity and temperature are big factors in bud density.
The spring rains are here, very humid, but where I am can grow outside all year round,
sub-tropics, never even gets close to a frost. Maybe minimum temp of 10C = 50F.