Why is the Grass Fields rated as an easier starting zone than the Rocky Desert?

I’ve run a couple games of Satisfactory so far, starting out on the two easiest starting zones, and I have to say I don’t understand why Grass Fields is rated as the easiest, introductory-level zone. In almost every way, it seems to be inferior to Rocky Desert:

• Poor-quality ore deposits vs. pure-grade ore at the starting zone
• More difficult access to caterium, oil, and (arguably) coal
• Water nearby is both less plentiful and harder to find
• Rocky Desert has thermal geysers on a plateau directly overlooking the starting zone, for when you finally unlock the ability to make use of them. For Grass Fields, the nearest geysers are waaaaaay out in the Blue Crater, near the horribly inconvenient oil field.

The only real advantage I’ve seen to a Grass Fields start is its abundant biomass, but biomass really stops being relevant almost entirely as soon as you get coal, and it’s not scarce enough in Rocky Desert that it was ever a problem for me, so it kind of feels like Rocky Desert is easily the better "introductory level" starting zone. But are there any factors I’m overlooking? Is there any good reason to justify the ratings as they are?