Gary KW4Z wrote:
...

Most, if not all, cb antennas came from others work in the past. The
1/4~ ground plane was in use in amateur communications long before cb,
so the yagi beam, the quad beam, etc., etc.

Indeed, I don't know how long it has been now since I have seen anything
"really new" in antenna theory, design, or construction ... a decade?
Two? Three? Four? More?

I think you will find most hams had the ability to build their own
antennas (knowledge, source of materials, help, etc.) and found that a
much more economical way to go. Plus, there is much satisfaction in
building ones own antenna. And, it is easy to produce much more robust
and quality when doing so, as opposed to manufacturers who have to pay
attention to cost at every level.

Regards,
JS