Light switch ground connection

Hi everyone, I apologize if this comes off as a dumb question or if it has been asked previously (getting conflicting responses).

Have a house I just bought, replacing all outlets and light switches. There are two electrical boxes, each have two light switches in them. Inside one of the boxes is four wires coming in (each wire has a ground, neutral, and hot, the other box has 3. Both boxes have all the grounds twisted together in a wire nut (not grounded to anything to my understanding). The box is plastic and not metal. I am putting in new light switches in these boxes, should I remove the wire nut and pig tail from all these ground wires to to one ground bolt on a light switch? Or am I safe to not ground the light switch.

Thank you