I've seen the OP's setup in the flesh, so to speak and the whole point is its simplicity. Chuck a hose over it, it reaches stuff without being snarled up. When finished, chuck the hose back down - it's not "dedicated" to the rig in any way and attaching or removing takes less than two seconds. There are no fastenings, ties, loops or cords to get diverted with and it is functional and elegant in a way that no boom or articulated device could _ever_ be. It's a stick, held horizontally. Being linear, it's always in the right place, without adjustment.
It cost hardly anything and it's not in the way.
This is Occam's razor instead of a five-bladed independently-sprung arthropoidally-contoured facial dehirsuitizing grooming accessory. Why complicate something and in the process make it less functional?
The Festool boom arm is a compromise solution for those needing a flying hose support for portable "out and about" use. It's attached to the dc to avoid attaching it to your customer's (etc.) ceiling. If you're using it in the workshop, using any sort of boom arrangement is surely missing the point by a mile?
Get thee a pole - a ROUND pole - and mount it at arm's length above your MFT, running from left to right. Chuck your hose over it when you want to use it, slide it off when you want the hose somewhere else.
If you want to make a super fancy deluxe version, put a length of drainpipe over the pole so it spins freely; simple, perfect, elegant, cheap, maintenance-free.
~Enjoy!!!