[lproven]

You may well ask, but you are far, far too late.

Red Hat already bought CoreOS in January 2018, some 18 months before IBM bought Red Hat.

The question would have been more relevant to either of those.

[wwright]

CoreOS was not a direct competitor to RHEL, it was intended to be a "next-gen" rearchitecture of the OS. No one was going to seriously consider using one in place of the other; if you were considering CoreOS, then RHEL was already off the table.

[type0]

It replaced Project Atomic for them, some parts from atomic ended up in core os though.