Having been in the room when working on branding, there's always plausible objections unless the brand is completely anodyne, and by extension terminally forgettable. At the end of the day you just have to go with something that isn't terrible.
And it’s not just the names — look at their logos.
https://en.wikipedia.org/wiki/File:ARC%27TERYX_logo.svg
https://en.wikipedia.org/wiki/File:Mammut_logo.jpg
The first one is straight up the fossil skeleton of the animal they based their name on! If that doesn’t spell extinction I don’t know what does.
These two companies make jackets, climbing harnesses, trekking shoes, backpacks and more.
I doubt that either of these two that I mentioned have been negatively impacted by the fact the animals they have based their names and logos on are extinct.
(My personal opinion is that it makes them cooler even — the prehistoric times and the animals that used to roam the earth are very fascinating to me. And I think a lot of people agree. Look for example at how popular the Jurrasic Park movies were. People love this stuff, don’t they?)
Mastodon = extinct elephant-like mammal
This is why successful companies hire marketers.