Morphos is using Objective C, why not AmigaOS.
https://www.morphos-team.net/guide/objective-c

OMG!! Yes that exactly how I imagined BOOPSI to be implemented properly! :agree

-edit- it looks like they have written their own Obj-C runtime, that’s quite heavy going... I use Obj-FW if I need a runtime on a non-gnustep/non-Mac platform!

That's not correct.

That’s a fair point! Microsoft actually adopted the strategy of keeping 30+ year old operating system components in their products. And it’s worked well for them. But this is certainly off topic, with little to do with BOOPSI.

My point wasn't about Microsoft, it was development continued beyond 3.1. Eg. OS3.5 and 3.9 have a full set of BOOPSI classes, which 3.1 lacks.

But the underlying architecture of how BOOPSI works has remained unchanged for 30 years! All the flaws and bugs are now part of the design, which (as meynef pointed out) has some advantages that they are at least known and work arounds have become standard part of the architecture, but also limits future development.

Well, I would not call them "bugs" (of course, we have that, too), but "design issues". They cannot be fixed anymore. We have the same thing in the dos.library with its Tripos legacy.