I always found it weird that someone with channeling 'earth' could make a skill replacement item without having ritual or Thaumaturgy. It's not explicitly forbidden in the rules...but it seems weird to me.
Based on the writing in the book, the implication of who can Craft what (and, the rule of thumb I go by) is that if you couldn't cast the spell normally, you can't put that spell into an item. Crafting items makes it easier for someone to take time to slowly build the spell and insert it into an item for later, rather than needing to do it all on the fly, but it makes
zero sense that you could create a gout of fire from an item if you couldn't do it with your mind alone. Anyone can craft foci or enchanted items, in my opinion, but you're limited to whatever types of magic you could already create.
Extending that House Rule, it means there is no Ritual: Crafting power. In the RagnarokNYC sequel, Babylon, DC, that will be the rule: if you want to craft
anything, you must take thaumaturgy. I
do allow people with only thaumaturgy to create Weapon Damage style items along the lines of evocation, though. It's pretty clear in the Thaumaturgy section that thaum can do anything evocation can do, it just takes more time.