Earlier quoted context omitted.
Trademarks are lost when they are not defended. That is entirely separate from fair use in copyright law.
This is an often repeated statement online (like “fiduciary duty”) that way over emphasizes the risk. Parody media poses absolutely no risk to their trademark, not even a tiny bit of incremental “damage.” Companies don’t need to be bulliest the vast majority of the time they act like one. We need to stop parroting this excuse for them.
A bit of a tangent to Weird Al, who often is said to not need the permission of the original artist because his songs are parodies, usually isn't commenting on the actual content of the original song but instead takes the lyrics and gives them a different theme. 'Smells like Nirvana' is one of the few songs he does that actually does directly parody the original. His videos are far more parody than the songs themselves. Makes me wonder where the legal line actually is drawn and if asking permission is actually because it would be too risky not to.