That sure is a big discrepancy. Not sure. Maybe Dynadot hasn't figured out their pricing yet so they priced it high so that no one will bother to buy it?
I mean it is not that hard to find huge differences in lots of TLDs although agree this one seems particularly extreme. That is why domain investors should always use tools like TLD-list, Domcomp, and NameStat that show various options to get an idea on what is reasonable. This is particularly true for thinly traded TLDs.
By the way Dynadot is by no means the highest - Name.com are asking $1599 today and Hexonet $1480 (both registrars with often very competitive pricing). We sometimes see big differences when there has been a price change that has not percolated through registrars but no idea if that is true here. To be honest I did not know there was a .voting TLD until this thread .
Also some registrars use a model with high prices and occasional time limited sharp discounts, and others use a more even model. The monthly specials at Name.com are almost always better than pricing of those TLDs elsewhere, but at other times usually some other registrar offer better deals, in my opinion.
But main line is - use the price comparison tools!