Something I have noticed lately, First startup idea that every Devops person starts with is to create a CI/CD project because they think world is inefficient and workflows can be optimized, and then they pivot to other ideas.
The slow changing nature of pipelines makes then candidate for not being touch once the configuration is set.
So, to answer your question, in my opinion - is there a room for improvement - yes, but the value is minuscule for a customer to switch to a different provider in CI/CD is working fairly well.
The economics may appear bad for not using GitHub, but there’s still valid needs for code that isn’t hosted in the cloud.
For those cases it is reasonable to see or know what’s out there.