This is absolutely a step in the right direction. GitHub permissions are ridiculously coarse-grained. Hopefully this will lead to more fine-grained permissions on GitHub in general.
Their pipelines was woefully underbaked and had tons of issues last I used it which was about 2 years ago. Pipelines was incredibly slow compared to Actions and was missing most of the features Actions has. You can't even define scheduled jobs from within the YAML file. You need to schedule them outside through the repository settings. It's also missing tons of triggers and the documentation is horrendous
I've not used their APIs but GitHub's is pretty huge. I highly doubt BitBucket's API is any better