"How about pangolins then? Or giraffes? I know, let's start a moment to protect all endagered species - including whales!" How is this "all endagered animals matter" a bad thing?

For what it's worth, I don't object to either "all species" or just whales. Regardless of whether someone is trying to protect all or focus their attention on one specific species, they're both working towards a good cause - though I do disapprove of the former trying to substitute the latter or vice versa.