You're right, but I think....that plant is committed. There is a real risk of killing it if it's transplanted it now. It might be fine, or it might die. I also think you should let it establish its roots, then transplant it, and never, ever use that type or size of cup again. I see another issue, the cup is clear. There needs to be some duct tape, or something, to block that light from hitting the rhizosphere (fancy term for root zone). Roots like it dark, cool, and moist. And it looks to be stretching, I would keep it as close to the light as you can without burning it. A small fan will help strengthen the stem so it won't topple over as it gets bigger. It's off to a good start, looks healthy.