So it's been asked and answered that an earth elemental can't drag anyone through stone as they don't have Earth Glide. That's fine it makes sense.
But, what if the person is tiny and the elemental can envelope them completely while travelling through stone?
And if not does that mean they can't take objects ever?
And the description for the ability says:
- Earth Glide: An earth elemental can glide through stone, dirt, or almost any other sort of earth except metal as easily as a fish swims through water.
This suggests that the elemental parts stone as water and an occupant small enough to be covered by the elemental could travel with them.
Best Answer
Size doesn't matter, Earth Glide applies only to the elemental
Earth elementals do not have the ability to "envelope" a creature to any mechanical effect. They have the exact same normal options as every other creature with regards to interacting with another creature which basically boils down to shove, drag, and grapple.
The fact is, the Earth Glide ability specifies what it can do and to whom and it only affects the elemental regardless of the size of a creature it might be attempting to carry:
This interpretation is confirmed as the intended reading by the Sage Advice Compendium as linked in the previous question:
There is no mechanical way for a creature to be "small enough to be covered by the [earth] elemental" in the rules such that it would allow it to be affected by Earth Glide because only the elemental can be affected by it at all. There is, in fact, no such thing as being enveloped or covered by another creature anyways outside of specific abilities like Swallow (which earth elementals do not have). And even those abilities do not allow the subsumed creature to be considered merged into the large one such that they are mechanically the same creature.
Simply put, Earth Glide affects only the elemental and no other creature, no matter their size, can be affected by it.
Your description is not from this edition
You quote a description for Earth Glide in your question:
However, you should note that that description is not from 5e and thus has no bearing on 5e rulings or rules. It appears to be from 3.5e (thanks @V2blast) which for all intents and purposes is an entirely different game from 5e.