XDR hubs and cassettes were/are not available locally and I can’t order them online due to the high costs. I don’t want to install things which are not readily available locally and have no warranty even though the price. And no replacements available locally if I’ll need to replace cassette or change it for any other confirmation. Shimano cassettes are always available in any configuration and cheap price. Same goes for my Brompton, all parts are always available locally.

So going the way you suggested with XDR hub/cassette is not feasible for me in my location.