Why is SMT (multicore) support hard for Amiga OS?

[dammy]

Yeah, I'm not suggesting that exec as it stands is suitable for "real" SMP, as you say, it would need a redesign from the ground up.

That's my vote. :-)  We need something modern that has the spirit of AOS but that would be a massive undertaking requiring a significant size dev team and funding for that clean sheet of paper.

[dammy]

Actually Haynie's PIOS-One mobo was a quad PPC CPU.