That its a systemic problem with RedHat's hiring practices; they allow remote but either their hiring tech stack doesn't allow specifying that or they don't want to advertise that.
I think it has to do with salary scales. Someone in Switzerland might demand a much higher salary than someone in the Czech Republic, purely because of cost of living. Anyway for this role, while it is remote, there are indeed some caveats (that would probably apply to any "remote" job). Firstly you can't just live in any country in the world, and move around whenever you want. For tax and export control reasons you have to live permanently in some country with a Red Hat office. Secondly you might be asked to come to an office during an initial probation period (although this will depend on specifics of the candidate and even the candidate's own preference).
"remote" has a lot of different meanings to different people; there is "remote, but we expect to see you in the office every now and then", "remote, travel to the all hands meeting required/expected", "remote, but most people are in the office so remote workers will be at a disadvantage", "remote, USA", "remote, $set of countries" (RH). "remote, employee in $country, contractor elsewhere", "remote, AOE". Only the last class of remote appeals to certain groups of folks, look up the #vanlife hash tag, or the tech nomad trend. Probably the person you responded to was thinking of "remote, AOE" as the only "real" remote job.
I found GitLab's documentation about how their employment stuff works quite interesting, they strive to have most people employees of GitLab itself, or one of its subsidiaries or affiliated companies and only resort to contractors when they cannot yet do that.
I've heard that before from other RH folks.