You definitely need cli for some stuff at least. Contrary to popular belief, cli is actually much easier for accessing and managing stuff. So most sysadmins and devops use cli at least to some extent.

Most servers and server providers only provide ssh access to ma age stuff, you can get some gui in more advanced panels to for example setup firewall, add ssh keys, open and close ports. You might expect a docker manager of sorts in some places. But since almost anything you can do with gui, you can do with cli, it’s considered an extra benefit if you provide the gui.

Some tools used are gui only though. They certainly use some sort of cli stuff behind the scenes but you can’t interface with their functions without gui. You certainly can do the same stuff with coding and running commands but why bother when the tool might be decent ane gets the job done.

All in all, it comes down to preference and more important than that, necessity. If you are an expert with cli usage and have a good memory or cheatsheet, cli is mostly preferable than a gui. Cli is much more standardized, there is no design change, commands might change but most of the time it isn’t. In gui you mostly get less data, but you can get charts. So in analysis mode, gui would be preferable.

There is no rule to follow, but since most stuff is only done using cli, you see it being used more often. Some applications are implementing better guis, some guis interface with a lot of application cli outputs, making it much easier to understand what’s happening. So you might get to see guis in action more often. You might have seen graphana for example in a bunch of movies. But I guess it doesn’t give the same hacker vibe as a dude with 50 terminals witg fast scrolling text. Which is useless but there are cli apps to do that as well.