It gets worse. GIMP also has an atrocious, screen hogging interface that was clearly designed by someone who doesn't really understand the workflow of most professional users.
I agree it has a strange interface, which seems to be different to almost any other app, but I would not say screen-hogging. In fact one of the advantages of the wirerd design is that you can have a full-screen image and float the various toolboxes in front as you need them.
It's also slow. Very slow. For example, a 64 pixel Gaussian blur takes twice as long in GIMP to compute as it does Photoshop, the same for most other operations.
I don't know how it compares with other apps but a 64 pixel Gaussian blur on a large image takes just under 3 seconds.
The text tool is awful too.
It's a fair cop - yes it is pretty awful - difficult to position text, size at anything apart from a point size, etc.
GIMP is way over-promoted by FOSS zealots who usually can't accomplish much more than cropping a picture and applying a few filters to the entire image.
There are some real artists using it.