Focused on “commercial” and while ignoring “political campaign, etc” misses the point. There is a difference between making up a new Chuck Norris fact and using the meme to support religion, brands, politics, or whatever.
Legal systems constantly deal with intangible abstracts like intent. “Pepe the Frog being co-opted” is cashing in on the existing work rather than operating in some hypothetical framework.
Pepe wasn’t officially adopted by that campaign, and its misuse and harm began long before and continued well after the press tied it to MAGA.
Beyond that, creative works shape society, and arbitrarily restricting them stifles creativity. Granting exceptions for reasons like ‘think of the children’ or ‘it’s just for the lulz’ fails to address the greater issue.