I didn't want to completely remove the roof rack, just the crossbars to alleviate the wind noise and the above linked video didn't detail those options so I got around to taking a look. You'll need a trim removal tool and a 5mm hex bit and accompanying ratchet. Shouldn't take more than 10 minutes.
Start off by removing the plastic decorative cover. Use a pry tool to reduce scratching. Pictured is only one side, but note on both sides of that cover is a small slot. Pry from both sides and the cover releases up.
Once the cover is off you'll be able to access the bolt. It's the only fastener that holds it in place (per side).
Once the bolt is removed it allows the crossbar to unclamp from the lower/inside portion. It slides towards the middle as pictured.
How it looks when opened up.
Repeat the steps on the other side and the crossbar simply lifts up. Just note that it leaves mounting holes on the inside of the roof rack. I'm short and the wife is shorter so it won't bother us.
It's the wife's and I had to get to work so I can't comment on the reduction in wind noise yet, but it was definitely there at highway speeds. Previous Mercedes also had a roof rack but without crossbars it wasn't a nuisance. We never found an opportunity to use it so I doubt I'll re-install them.
Hope that's helpful.