I almost want to agree with parts of this but I cannot imagine the downvotes for supporting a comment that includes “never hear about Jenkins” and “don’t learn Docker”.
Jenkins has about 50% market share for anybody keeping score at home. In many verticals, the market leader has about 35% market share so 50% gives Jenkins enough domination in the market that saying “never hear about” them is going to hurt your credibility.
I think most organizations using Kubernetes should not. However, most of those would still benefit from containerization and so knowing Docker is a good thing even if you use a different tech ( Podman is the same thing ). While I think people should not be using Kubernetes as much as they do, it is still going to help you to know it when you are asking those people to hire you.
Knowing Python is fantastic advice for DevOps and IT in general.
Ansible and Puppet are solid recommendations. I think Ansible is the market leader ( probably about a third ).
Keycloak is great but it had less than 5% market share and so not knowing it is not going to hurt.