Nobody is arguing that DevOps and SRE are brand new. But saying "sysadmins were doing then what SRE does today" is a bit like saying "builders in the 1500s were

Nobody is arguing that DevOps and SRE are brand new. But saying "sysadmins were doing then what SRE does today" is a bit like saying "builders in the 1500s were doing what builders today do". Yeah, they're building houses, and trying to make sure they don't fall on somebody's head. But the practices are quite a bit more developed now, and the old-school people don't know what the new-school people are doing. So it's still worth learning and separating from what came before, because the advantages of the new practices outweigh those of the old.