I'm all for the headless CMS space, but I'll never recommend a solution to my clients that causes vendor lock-in and that I don't have the ability to operationalize myself.
Most folks in this space, wordpress included, follow a model of "open source, but pay us to scale and operationalize it for you".
They follow this model because it works.
As a CTO making decisions for my company, I'm not going to take the risk on a startup in this space without an open source fallback plan.