The Austrian military didn’t just adopt LibreOffice; they actually contributed back to it. Over five person-years of development work went into adding features they needed. Those improvements are now available to everyone using LibreOffice, which is pretty cool.
You’re right that Photoshop has features incorporated into it which GIMP doesn’t. It’s worth remembering though that although GIMP follows the unix philosophy of not trying to do everything it does do a lot to interoperate with other software. For example, if I want to open a RAW file directly from GIMP, it launches Rawtherapee or Darktable for me, which processes the file and then opens it in GIMP, much the same as an Adobe workflow but more visibly two separate programs working together. And of course there are G’MIC, Batcher and Resynthsizer but they do need to be installed manually as plugins, which is not ideal for newcomers.
I think a big game-changer for some users is going to be the upcoming release of ‘Link Layers’. You’ll be able to have a layer in your GIMP project which is linked to an external file. So for example you could have a layer in your GIMP project which you are editing Krita.
I’m sure a lot will depend on what you’re working on but in my workplace the only thing really holding us back from switching to GIMP is setting correct scaling and position for printing on rolls on Windows 11. If I could get my boss to switch to Linux (probably even more amibitious) we would be done with Adobe.
Curiosity apart, the intelligent object removing in PS is also based on the Resynthesize, which is a invention from GIMP. It it used now also by other editors, even in online versions, like eg.Lunapic, there called “Remove and inpaint” in the seleccion tool.