There are similar boarding processes: (not exactly the same) as described by the OP in airports around the world.

HKG is one. Some of the larger China airports do the same. LHR has this multiple-lane concepts. Melbourne too. All the examples mentioned have either 2-door gates or two lanes process at the podium. Sometimes, they do it at SFO as well when they try to get planes out faster.

What OP described is a bit different. Each gate door leads to separate jetway vs those lead to a common area before spliting two separate jetways.