First, it is not "section 15". It is Part 15 like Part 107 of the FARs. Minor point, but worth being accurate.
I do not know the details of the two situations you cited. I don't know which "waivers" you are referring to either.
However, if they were using their own equipment that they certified then they can use any antenna they want to if that is the one the device was certified with.
I also have no idea why the FCC does not more rigorously enforce their rule. However, a lack of enforcement does not mean the rule no longer applies. The FAA certainly has not rigorously enforced Part 107 and prosecuted non-compliant pilots, but I don't see anyone saying that means Part 107 requirements can be ignored.
Again, you seem to be attempting to use the "they don't enforce it" or "other people do it" as reasons to justify not following the FCC rules. Why not simply say that you are choosing to ignore the FCC regulations and leave it at that?
Each of us is free to decide what we want to do with respect to any FAA, FCC, or any other regulations.