I went for a towbar carrier even though I don’t intend to tow anything - but handy just in case. I paid just over £500 for a quality Westfalia removable bar (originally Westfalia tow bars and camper vans were part of the same company and are still next door to each other in Rheda- Weidenbrück).
I bought the Mercedes 3-bike carrier (which is made by Atera in Germany) from Mercedes in Germany and is cheaper than buying in the UK. They only charge €7 for carriage and you can return it FOC if you don’t want it! They are on offer at the moment for €559.90 (probably about £500 depending on current exchange rate).
Also, bear in mind that not only does it fold, but you also get a free sturdy canvas bag ,from Mercedes Germany, to store it in which costs at least another £50 in the UK. The tailgate does clear the carrier (just) when it’s lowered, especially with the bikes attached - the weight of the bikes helps to keep it clear of the upright rail.
I’ve used the VW type tailgate rack before (on a California). OK if you have light bikes. We use two full suspension mountain bikes which are much easier to attach at the lower level of the towbar carrier. Also, the bikes do not protrude above the roof which is a significant advantage if you want to use car parks with height barriers. I nearly came to grief a few years ago in the California when driving through a low underpass, forgetting the bikes were on the back. A passing motorcyclist indicated, by way of grimace, how close I’d come to ripping the bikes and rack off the van!
Another consideration of mine was that due to our advanced age (late 60’s), despite good fitness levels, the time may come for the dreaded electric bikes. The Atera carriers will take the weight of a fairly typical electric bike. Try lifting one of those onto a rear mounted tailgate rack!
For me the towbar carrier at about £1,000 for quality is a no brainer and you can of course get a towbar for a lot less as well as a cheaper carrier. When I’m at home using the MP as a daily driver I can remove the towbar and not have to continually stare at a permanent bike rack through the rear window.