We agree on this one Tom - M lenses for M body - and basically it's best to use lenses on the system which was designed for them!For me its a Leica M body for M lenses. The other option would be a SL which I would choose if I wanted to shoot with 75 and longer or with a Noctilux.
But the real joy to shoot M lenses is a M body. If I wanted to use a Nikon Z body I would rather buy one of the great 35 and 50mm Z lenses and sell the M lens.
Have a great weekend