As a general rule, having some sort of all-powerful role (or user) is probably poor design. However, practicalities should be taken into account.
The root user on a Linux system is all-powerful on that server. They can do absolutely anything - read/modify the RAM or files in use, or shutdown the server or anything else. You could well argue they're a "super admin", and we do generally refer to the root user as a super user.
However, that root user cannot do anything to other servers, or the network infrastructure or anything else "outside" the server in question. Thus, they're not a "super admin" of the whole system - just of that one server. This is an example of segmented access - which is absolutely something that a new systems design should incorporate.
The principle at play here is to allow a human to do the work they need to do (especially in an emergency), but not to allow the human to do more than that. If there's a problem with Server1, then they can do whatever they need to fix Server1, but can't go and mess with Server2 (to work on Server2, they'd have to authenticate again, and separately with Server2). The point being that just because they somehow got the credentials to log on as the super user on Server1 doesn't immediately give them the ability to do it on Server2 - so they can't accidentally do something to Server2, and nor can a hacker use one point of entry to move "sideways" into other areas of the system.
Moving on to non-emergency situations, you have to allow administrators (and users) to work on the system. For that, you'd ideally want to give them a reduced set of permissions, so they're not a "root" type super user anywhere, but can still perform the likely maintenance and other activities that they need to do. This is generally called the Principle of Least Privilege, where you give people just enough permissions to do their work, but nothing more than that (and ideally no where near enough to do any damage).
Assuming an administrator is using their least-privilege credentials/account, then they can do their normal job. However, if a non-normal task comes along (like an emergency, or a special request), then they can (temporarily) elevate themselves to a higher level of privilege (perhaps a super user). This "elevation" step should be an explicit action so that it's something they must have deliberately done, and couldn't have done accidentally (you probably want to log that it's taken place too, so you have an audit). The point here being that if they go on to do something bad, they can't claim it was an accident, or their finger slipped or whatever. When they've finished the special task, they should go back to their normal (restricted) level of permissions. To that end, some "privilege elevations" are time limited so you have to keep renewing them if you want to stay in the higher level - as a means to avoid having people stay at higher privilege indefinitely.