There is a youtube video in the comments with a recreation of the vector image from the original graphics:
Root cause: The Amiga didn't have curves in its graphic primitives.
Just this week i read an article in a 1986 Byte magazine which included a comparison of the Amiga and Macintosh graphic privatives. The Amiga had color routines, but the Mac had circles, curves, rounded rectangles, and a few other desirable shapes that the Amiga lacked.
Except for the text, the Kickstart image is not a bitmap, it's the output of a vector drawing program using the built-in ROM routines. No curves, and that's what you get.
Edit: September, 1986, page 251.
How funny, I've been on an 80s Amiga Cracktro/Demoscene kick this week and it is an image frequently seen and tweaked in many demos.
https://www.youtube.com/watch?v=50WWFEBsgfk
https://www.youtube.com/watch?v=pssH6moTGLc
(I couldn't find the specific intros with the funny graphic...)
An unfinished, but "sorta working" attempt to recreate that vector drawing data onto an html canvas.
https://jsfiddle.net/kw4b95gv/4/
I didn't do the color flood fill, and something isn't quite right, but it's recognizable.
Tossing my JS implementation onto the pile as well, I guess. Missing the flood fill command; picked the wrong graphics library for this and it was too late by the time I'd realized it. ;) Easy enough to change over to something else, but it's time to move on.
I never would have guessed that the Kickstart 1.x graphic was vector, but it’s so clear in retrospect. It’s not hard to spot the nodes of the pre-Bézier shape paths once you’re looking for them!
Bad? What about iconically good? Instantly recognisable definitive Amiga ... that's good isn't it?
It also has an odd mix of anti-aliased text and non-anti-aliased. Additionally, I don't like the aspect ratio of the floppy disk.
For me mostly the aspect ratio looks too wide. Not sure if it also looked like that on an Amiga monitor, did it have square pixels?
What’s even more impressive is a basically identical graphic was in the 8KB A1000 boot ROM, to ask for a Kickstart disk
If you want to see what the image would look like at high resolution -- I couldn't resist making a small JS implementation: http://ianhenderson.org/kickstart-vector.html