I really like & support the .40Super caliber as a duty/sidearm/defense pistol but it never quite caught on in CONUS.
Overall, the 5.7mm round has merit(large ammo cap, low recoil, deep penetration, aim) but it's not popular either now. 2020? 2030? Maybe.
The small arms/PDW research has been going on for decades.
R&D in NATO or milspec weapons takes a long long time.