Depends on what you're creating.The iPad can easily replace casual computing needs (web browsing, email, online purchasing, online banking, facetime, messaging and so on).
But as soon as you want to create something, you'll still need a computer to do it efficiently, and to have access to professional software with an efficient workflow: Photoshop, Lightroom, Premiere, Capture One, Final Cut Pro X, XCode, Visual Studio, Logic Pro X, ProTools, all types of software development (Perl, Python, C++, C#, C, Swift, etc).
Excel/Word the iPad is still a nice choice
Programming - go over to the iPad forum and it seems there are a number of developers who like to write code on the iPAd
Lightroom - Adobe has been improving LR for iOS and you can see most of the focus is iOS and not desktop
Photostop - Likewise with my comments above and there are other competitors that have some really polished products for iOS
Yes, there are many things a laptop/desktop can do that the iPad cannot but I don't believe the consumption vs. creation demarkation is clear as it used to be. That line has blurred over the years. I for one still need a laptop/desktop because my iPad cannot do what I want it too but I do see the iPad gaining as time marches on