I think the only advantage it has is that it includes the ability to make screen captures, in addition to taking screenshots. But as some people have pointed out, it doesn't record sound properly.
On the other hand, it doesn't have the ability to specify a delay like the old screenshot tool does:
And since it's not a utility that you can run from the command line, you can't create custom keyboard shortcuts to create such a delay yourself. The only option I can think of that could do this is writing a script to simulates keypresses. But is not a very elegant solution, and cumbersome.
Unfortunately, the only option is to install something else like flameshot or gnome-screenshot that have been mentioned.