I don't know where to start in how Inkscape gets everything wrong. I suppose I can start off with what it gets right. I like the complex grid controls. I like being able to simply warp a shape onto a path. I like the slightly more advanced bitmap export options. But everything else is god-awful (speaking as an atheist, I can assure you that that's pretty bad).
I can't wrap my head around the design choices. What logic went behind the keyboard shortcuts? In Blender, for example, there was a very specific point to make useful functions rest on the home row. In Illustrator, there's a clear decision to keep the letter keys generally uncluttered with functions and use Control+ functions (and organize similar functions as Control+Shift or Control+Alt in a fairly consistent manner). Inkscape just throws logic out the window, with the apparent philosophy that if there's a key, it should immediately do something. There's no mnemonic or sense behind it. Alright, what do you think the "I" key should do? Well, in Illustrator, there's a handy little mnemonic: I is pronounced "eye" and is used to select the eyedropper tool. But press I in Inkscape and you get the spiral tool. Why in the hell is there a spiral tool? Why does it need a hotkey? It's probably the most useless tool I've encountered and it doesn't even really have any great functionality. Once you do track down the eyedropper tool, it turns out it's also totally useless because it only copies the color below it into the fill, no matter what other effects and properties could be copied.
But despite having a shortcut to make an impossible to edit 3D box (why, again, does this need a tool at all?), shape editing controls, while they exist, are not only obscured away in an online documentation (because apparently Inkscape developers would rather not have their dropdown menus cluttered than they would have to stop working to go look up shortcuts), but they're unintuitive. Granted, there's no great reason to use Adobe or Corel conventions (okay there's a great reason not to use Corel conventions, they suck), but in Adobe's case they have a pretty complete suite of software that generally follows the same standards. Ctrl+0 views full screen, Ctrl+Shift+ does the opposite of Ctrl+ in most cases (so Ctrl+Z does undo, while Ctrl+Shift+Z with redo), &c. across most of the software they make. Open Source doesn't seem to have standards. The entire community appears to be made up of idealistic nutcases with arbitrary standards of interface perfection that necessarily cannot overlap with anyone else. Why, when the rest of the world as long as I have been alive uses Ctrl for functions, does Inkscape have to use Shift? There's no good reason and it's infuriating.
Even with unintuitive keyboard controls, I could probably get used to them if the mouse controls weren't inspired by the sensation of performing oral surgery with your instruments tied to the ends of pool noodles. Nothing makes a lick of sense. By the way, did anyone think that
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I could go on about the text editing tools, window layouts, nonsensical icons, crummy performance, &c. all day, but it brings back bad memories of using your broken software. I'll just close by saying congratulations, you've effectively killed my ever bothering to use Open-Source software for graphic design again. That makes me kind of sad; I enjoy MyPaint and Blender, and Audacity gets the job done, among others, but I've never seen and OS Alternative that would convince me not to spend a few hundred dollars on functional software instead. I went in using Inkscape to do a quick commission and finished having to start everything over in Illustrator because it edited so badly and the end format was so useless. I'm disappointed.
Let the empty retorts commence.