The last few B2B/SaaS projects I worked on had CI/CD built into the actual product. Writing a simple console app that polls SCM for commits, runs dotnet build and then performs a filesystem operation is approximately all we've ever needed. The only additional enhancement was zipping the artifacts to an S3 bucket so that we could email the link out to the customer's IT team for install in their secure on-prem instances.

That sounds like the biggest yikes.