Agreed. You’d think a hardcore bitcoiner like NVK would be loathe to make such a petty intellectual property claim. Seems very fiat.
While I sympathize with the argument that trademark law requires enforcement, Blockclock is such a generic name that a trademark should have never been issued. Equally, displaying Bitcoin data like block height on a screen is an obvious idea that certainly doesn't deserve protection.
Notably, the term "btcclock" was coined 7 years ago by rcassata, for essentially the same idea: https://github.com/eternitywall/btcclock
There's nothing wrong with another project choosing to use that generic name for yet another implementation of the same idea. Coinkite should do the right thing here and withdraw their takedown.
Discussion
If it was a good intellectual property claim like a GPL violation or an original trademark I'd be fine with it. It's not.