earth is in the goldilocks zone for water, and also has a complete set of all of the elements availible everywhere,and also has localised temperatures from refractory to near cryogenic,
ie: in siberia you have to heat the propane in your extream off road rig, or it freezes@-60°
we also have surface pressures that vary from
so low ,that life is tenious, to so high that life is impossible.
All of this points to an almost infinite number of possible habitats and nitches for life to exist or originate in.Here.
A basic rule of life is that any nitche will be filled and competed over, more edges, more species,more energy exchange,more competition,
more more MORE, not neat, not tidy, not nice,
Ice moons are going to be vastly simpler, and less energetic locations for life to exist, and if we do find one, localy, we will mine it for its yummy volitiles, and turn the rest into a salmon farm, yum.The Japanese will pay anything to set up
exclusive hotels on an ice moon serving alien sashimi, no matter how tiny and strange, as its already one of there cultural norms.
Hungry now.