Really? I was a DevOps engineer a few years ago and can't really imagine a useful tool in that category so I'd appreciate a few names I could check out. While I've switched to frontend development, I'm still interested in CI/CD and just can't imagine any tooling being able to make it easier then what we had back then too (ephemeral envs using docker-swarm/k8s and pipeline triggers, basically)
https://www.withcoherence.com/
These exist in the B2B space (and isn't an exhaustive list), there are a ton more in the B2C space
So we went the "build-then-buy" route with Netlify. AFAICT in hindsight, what we built was more stable than Netlify, and had the same interface for devs, basically. (… and might have been operationally cheaper.)
(It's all moved to an -and-buy-another-different-thing-for-no-real-reason-other-than-different-people, now.)
It's even possible with good old Terraform, used correctly.