Mostly mission critical server that I deployed in the past, all use RHEL/Clones because their LTS, and stability across packages version.
If for hobbyist, it’s Ubuntu. I think you need to learn more about ansible, container/podman/openshift, and SDN for work. Nowdays, there are some use APT in production, but mostly they switch to dnf because dnf have better way to do downgrade, undo, redo, and config package in production.
This applied mostly for ERP project such as SAP Hanna, SQL Server, DB2, etc… Like it not, Red Hat Dwindling isn’t now, probably 5-10 years ahead, but I’m not sure, as mostly rant about RHEL are in Community. I do know regional linux user group in Indonesia, some are leaving EL group, but they still can’t rip apart most mission critical server on top of RHEL/Clones… so it’s still worth learning RHEL/Clones, and use Fedora for day 2 day task, and learn ubuntu, as well ubuntu pro, for learn deploying critical production server.
Debian and Ubuntu are near, and ubuntu is derived from debian, but if you talk spirit, they are different… If you are conscious about what Red Hat do, stay away from it, but if you are working in corporate, you can’t go without learning it.