They could've just improved Alpine's supply chain (or built on top of it) rather than making a new distro :( But they're a company, so pushing out new products faster is more important than the community.
We still work with them upstream on apk and apk-tools, and would be happy to collaborate on more tooling.
But we heard overwhelming demand for glibc support from customers. So we built a companion distribution for customers who needed to run GNU/Linux workloads, but still wanted to leverage the advantages of Alpine.