The new timeline isn't a hard reboot. The timelines are SUPPOSED to be identical up to the point Raiden recieves his visions in MK9. That is the premise. Any contradiction to that is a continuity error.
Also, NRS is a terrible company, and I have proof to back that up:
https://variety.com/2019/gaming/features/netherrealm-studio-warner-bros-games-toxic-1203204728/amp/
Read all of this. Read it very carefully.
Netherrealm Studios is a hive of scum.