One of the arguments I've heard against this is that it makes software feel like a "cheap clone". If most features are here, but there are a few missing or slightly different, you will resent their absence, or notice the difference, and conclude the clone is "incomplete" and inferior.
And indeed, it would be very hard to make a perfect clone, but it may not be desirable either. There may be better ways/tools to achieve the same results, and if you just look for the features you are used to, you'll never find them.
I haven't used Photoshop in years, but regularly use GIMP. It was not always intuitive, but now that I'm used to it I find the workflow quite effective.
Since we are talking about cloning, a good example is the clone brush / stamp. In Photoshop it’s it’s own tool. In Krita (and perhaps GIMP?), it’s just another brush you have to dig for and find, and adjusting the clone settings is very annoying.
This is a common occurrence, where you will google for “where is X in Krita / GIMP”, where X is a very regular tool that for some opaque reason has been stuffed away in a very strange place. Photoshop stores their glassware in the cupboard? We better keep it in the fridge!
I hope that at some point Krita or GIMP or maybe even a unified Paint.net+Pinta gets a Blender moment, where a few bigger companies are tired of paying gobs of money to (mainly) Adobe and start to pay for development.
I think what you are looking for in GIMP is the Heal tool[1]. It sounds a bit like the xyproblem[2,3]: what you want is a way to erase part of the picture, not "the clone/stamp brush in GIMP". It may also be related to the "curse of knowledge" cognitive bias, but you have to unlearn some of what you already know (and doesn't apply here): having a different interface is supposed to help a bit here.
I understand why you'd just want "photoshop but free", but there are a lot of reasons why it would be complicated to obtain, if achievable, not to mention... desirable?
Regarding the heal tool, on my UI (2.10.34) I have to long-press the "clone" button, next to the eraser, to get it. Now that I mention it... the "clone" tool [4] may be what you are looking for? I tend to prefer the heal tool though. The "clone" tool was here since ~2004-2007 (timespan of the 2.2 version) according to the manual[5], which makes me question your memory, though.
Krita is more of a painting program than an image editor, so this tool is less needed. I am also less comfortable with it, but I found the "smart patch tool" [6] in under 30s of looking up "krita remove part image" in DuckDuckGo. I also found references to the clone brush, so I looked for it, that sounds more like what you describe[7].
Anyway, I don't want to attack you or anything, I would just like to point out that in general, when switching tools, it's better to look for the idiomatic way of achieving the same result, than a 1:1 equivalent of every step.
One of the arguments I've heard against this is that it makes software feel like a "cheap clone". If most features are here, but there are a few missing or slightly different, you will resent their absence, or notice the difference, and conclude the clone is "incomplete" and inferior.
And indeed, it would be very hard to make a perfect clone, but it may not be desirable either. There may be better ways/tools to achieve the same results, and if you just look for the features you are used to, you'll never find them.
I haven't used Photoshop in years, but regularly use GIMP. It was not always intuitive, but now that I'm used to it I find the workflow quite effective.