I also wonder if your viewpoint has any room for forgiveness? When I got a friend to try the Prepare to Die edition on steam, it worked without any issues (he used a controller though), he didn't even need to install DSFix, so clearly through patches they made the port acceptable. The 'Remastered' version also works without installing anything extra (except on Linux, you need to install a dll yourself) plus you get reliable 60 FPS. I don't know what Dark Souls 2 or DS3 looked like for PC gamers on launch day but when I got them I had no problems, but I don't know if they would pass your criteria or signal a sign of improvement.
What amazes me is why the Xbox 360 port was so bad with respect to framerate in one particular area. Even the Xbone X drops down to 15 in a small portion of that area (but at least is rock solid 30 pretty much everywhere else, unlike the 360 or the classic Xbone emulation).
Sure, when they patch the game themselves so it isn't broken. Since that hasn't happened and likely never will happen, I'll take my money elsewhere.