I'm also OK compiling my own bitcoin-qt or whatever, I'm just concerned there are many outdated packages as of late, and what makes Arch so special to many people is the rolling release part and up to date packages. It seems legitimate to expect the package to be up-to-date given it may be bothersome to compile it, this isn't Gentoo after all. However, that goes both ways, as was said, the maintainer may have reasons for which it wasn't compiled yet.
As such, I suggest you use a new bitcoin-qt-bin package, basing on these instructions (https://bitcoin.org/en/full-node#other-linux-distributions), simply changing to install to $pkgdir/usr/bin, using the binary package digitally signed by the project itself (https://bitcoin.org/en/download). You can add it to the AUR if you believe others will profit from it as well. It will be almost as fast to install as using the official repos, and will always be up-to-date (as long as you know there's a new version). There will be no compiling hassle. Hope this helps, João Miguel