A humble 737 (well maybe NOT a 738WSFP. .that is a bitch ! ) can easily do the equivalent of 6 degree approach I.E 10 miles 6000', but. . that is assuming you drop the gear & all the flap right through to 40 at the limit & then fly at the limit for F40-5KTS (either manually or automatically if you can REALLY use that MCP . . & so few can regretably ) till the 1000' or 500' gate. Done it a few times due either my own, or ATC's misjudgement, but always with a defined moment to say "game over", and always keeping my colleague in the loop.
These AF Jokers were so far out of these parameters that they were not operating to any pre-rehearsed "recovery scenario". . they were just hoping that Physics were somehow having a "left-field" day.