Executive summary - meh
I just flew LH biz class from Canada to Germany. Their biz class is really below average, not competitive with other major airlines.
Swiss Air and Austrian are part of the Lufthansa family, but their business class offerings look significantly better (depending on the plane).
I posted a query re: Lufthansa biz a while back on Reddit r/Lufthansa. Response was yes, the hard product is out of date, but Lufthansa never scaled back the soft product (food, service, amenities) during the plague like US carriers.
Lufthansa biz is layed out 2-2-2, so a couple flying together may be just fine. Single flyer wanting lots of privacy not so much. The center section should be better, since both seats have direct aisle access.
On my LH flight in biz, I was served inedible food. Really disgusting. Thankfully, I ate something in the lounge before the flight. In addition, the cleaning was not thorough, which was a big No No during the pandemic.
Swiss and Austrian are indeed MUCH better. The service and seats offer more privacy. Their food/service is far superior. In fact, in Austrian's long hauls, there is a chef on board.