I recently left Red Hat (Feb 2021). I joined from the CoreOS acquisition in 2018. For the most part I enjoyed working at Red Hat. Honestly the real reason I left because of GME but there where a few things that convinced me to move:

1) Killing CentOS/CoreOS. Replacing these two stable OSs with unstable upstreams in CentOS Stream/Fedora CoreOS.

2) So many container tools that have overlapping tasks yet perform in completely different manners (podman, buildah, cri-o, skopeo, tekton, openshift, quay, libpod). Interoperability between all these projects was a constant struggle.

3) Forced usage of IRC. I shouldn't have to run my own bouncer to get features like history, push notifications, identity services. I cannot comprehend how in 2021 at a major corporation I would receive irc messages from usernames like "cloudpizza9000" or "m0use" and be expected to know who these people are and take things seriously enough to work together. It seemed like I was in a 90s chat room with a bunch of strangers.