Yes, and that’s actually also a problem for demons.
See discussions in this forum about spawning half demon children on low mana planes to help gather mana to summon (and return) their parent.
If you come from a mana rich place you can pretty easily get anywhere (if you know where it is); but once you are there…getting back is hard.
Now this is why…actually…old fashioned, mana draining Astral travel is often best. If you can summon up enough mana from your home plane (or the destination plane) you can create a corporal body on the remote plane (very expensive/difficult spell/discipline–you’ve gotta be burly) you can then have a body on two planes, and you can go back and forth between the planes simply via astral travel and follow your astral cords to the other bodies.
Now there are some definite dangers in doing this, there are whole treatises on doing this and how dangerous it can be but…it is one way to get somewhere that might otherwise be difficult to get back from.
However, for most Astlanian Wizards, the Earths are just too far away, the laws of magic/physics too different. Whatever it that makes them myopic to people from “Earth” for example, makes them very hesitant/makes it very difficult to asterally travel there, and body creation is prohibitive but…
All that being said, the Gods don’t seem to have a problem on that front…but then, they tend to be hardwired to their God Pool and can draw on that anywhere.
I really wish I had a god pool. Actually, I really wish I could just use magic of any sort. Being a Fiend isn’t easy.