It was in the AUR to begin with in 2015, then at some point was imported to Arch. It was dropped back to the AUR last November. There could be various reasons why Arch decided to stop maintaining it.
The most common usually are:
Upstream stopped development
The package no longer builds and upstream did not respond
The Arch Package Maintainer no longer found it viable to package
If you want to continue using it, then yes of course update it.