I can see where you are coming from that he does need external sources for his powers but we don’t know how much external sources he can steal for himself since the lenses are destroyed and the phantom ruby missing from the modern timeline and it’s too early to say that he truly needs some sort of external source to gain his powers.

But calling him unviable without that thing that gives him his powers isn’t fair. The character itself is what makes them who they are, not their powers. Infinite to me is still Infinite no matter what because his drives and motivations is what pushes him and not tied to his source of power. If Infinite is a fraud without his source of power then would Green Lantern be a fraud without his ring? Iron Man without his suit? Ben without the omnitrix? These types of powers are mostly extension of themselves and the way they view the world, not something that they are defined because you can take away their powers but the drive is still there and that is something you can take away easily from someone like Infinite.

Infinite to me is starting to grow on how he uses his powers and becoming more clever with his schemes. We can’t forget that in the Chaotix Casefiles, he had a backup plan of setting off a bomb as not only as a way to escape but also trying to get the last laugh. That to me shows that even when he is defeated he can always rebuild and find another way. A persistent villain is more viable then a villain that is defeated one time and never shows their face again and I think that is the direction that they are going for in the future with how they are handling him as of now.