>>9005657Gundam series were always like that, even in Japan. They only made a proper toy of Gundam when the anime originally aired, and even though the creators loved Zaku and wanted it to be the only enemy MS for the most part, executives said no and made them have a more monster of the week style Zeon MS roster.
The grunts gained popularity gradually over time, and those older fans now are the ones mainly buying them now. It's why newer shows are 80% gundams because newer fans even in Japan go after the gundam faces.