Lead maintainer of Pixie here.
Pixie will remain licensed under Apache 2.0. We are also working on moving Pixie over to the CNCF, to maintain this guarantee. This is being tracked here: https://github.com/cncf/toc/issues/651
In addition, we will likely move to a DCO (Developer Certificate of Origin). We are still trying to figure out the exact logistics, but this will allow commits to happen without signing a CLA.