shouldn't this type of connection be called 422?

RS422 and RS485 are, for all practical purposes identical as far as the signals go. While RS422 is somewhat more linited electrically the transcievers used for 422 has for ages been 485 making the lines identical. The real difference - as far as the standards go - is that 422 is point to point full duplex and 485 is multipoint half duplex.
A lot of bastards have popped up, e.g. J1708 uses 485 drives while destroying the balance of the line, some use 2 pairs as 'master line' and 'slave line' some do multipoint 4 wire etc.
The origin of some of the bastards is that 422 was used as a long distance 232 (full duplex point to point) and for some applications grew into multipoint where the full duplex has only extremely limited advantages.

So RS485 is one pair multipoint (can, of course be just 2) and RS422 is point to point 2 pair. Anything else is neither.

Erik