I think because most of giantess content makers are not faithful to giantess way.
Many of them changed their way just for more money by making other stuff instead of improving giantess works , like making small women , giant men , extreme muscle growth , Vore and ...
but some artist Like Dragoon have their way from the first till now and their works are lovely anytime because they are moving on a line and try improving it everyday not adding more themes and stories and ... only for more money ,and artists like Dragoon or Bmtbguy or ... understand art
