I agree with this criticism, but I wonder how they could monetize without locking in users. I suppose they could open source their toolchain so anyone could stand up their own Dark framework on-premise and maybe they sell support and/or a managed service and/or "enterprise features" (whatever those are in this context)? Maybe these things will come sometime after the private-beta (perhaps they're just getting a better feel for their product's value proposition before committing to opening any particular piece of it up)?