Do you really need VC money to put a proxy in front of other APIs? For what exactly? Marketing? What exactly you want to maket? You're already known.
Infrastructure? For proxying requests more infrastructure? You could just pay Cloudflare.
More engineers? But you yourself are the stret seller for the same snake oil that engineers aren't anymore necessary
So what that 100 million dollars are for?
ig this reply by co-founder of openrouter is relevant: https://news.ycombinator.com/item?id=48340940
They are because they can, because it serves as social proof, which convinces their customers that they are doing something of deeper value. Then in reality they will use it to develop channels preparing to use their customers (and the data customers trust them with) as the product in the future.