exe.dev has quickly become my platform of choice for hosting, testing, playing and tinkering. I haven't had this much fun playing with a providers offerings since VMs were a new thing. You have no idea what you're talking about here and should do a little research on them first. What you are saying they are, is not that.
Yes exe.dev is the first cloud provider I actually enjoy using. It's easy to manage with just ssh and they give me real disks. The lack of real (EBS is still networked) persistent disks on ec2 instances causes me a lot of pain at $WORK.
https://exe.dev/docs/shelley/llm-gateway
"The exe.dev LLM gateway provider source within an LLM integration remains supported. It provides exe.dev-managed access to Anthropic, OpenAI, and Fireworks models. Your subscription includes a monthly token allocation, and you can purchase additional tokens at https://exe.dev/user/shelley."
The access to closed platforms is managed according to the docs.
You don't need to use the LLM integration at all if you choose not to and even without it, it's a lovely service.
I've used the LLM only a few times to make a few sysadmin tasks easier that I could have easily done myself.
And? It's a convenience for their users (and most users for sure want this) for easy access to frontier closed and also open models (Fireworks). They advise also there is no markup or profit made for them in providing this managed gateway.
I guess I don't understand the OP's point even. Is there some conflict with providing this service and still being passionate about open source? IMV the answer is no.
Their main software product, Shelley, is open source: https://github.com/boldsoftware/shelley