Is it dangerous to put outlets without grounding if there is land in the apartment?

Hello! Help with advice please: I replaced a friend with two outlets in the apartment that were grounded (yellow wire) with outlets WITHOUT grounding, insulating the wire without connecting it to outlets. Now I’m worried about whether this will affect the fire safety in the apartment in the future, or is it better to buy sockets with ground and connect as it was. How much land is important in this case. Thanks in advance for your reply!