If torquing to spec, you need to know if that spec is ungreased or greased. Greased or not makes a large difference in torque for the same amount of fastener tension (what matters most).

No question greasing lowers the friction. But I don't know if that is a given it will accidentally loosen easier.

For example, on pedals it is always recommend to grease them. But the nature of pedals with the respective right and left hand threads, is the loads we place on them are continually working to tightening them. Of course many other bolts like a seat post clamp are not rotating and nothing is trying to tighten or loosen them.

My own experience, I can't remember having any bolt or nut on a bike loosen becasue it was greased. This is assuming it was torqued to spec to start with.