it was mostly marketing "oooh altivec can do sooo many FP calculations that it has to be licensed as a deadly weapon". Same kinda marketing for MMX "if a programmer was an a MMX guru then basically you have a supercomputer bro"

That's all great but it was all awaiting a killer app to make it all worth it and reasonable, versus random programs rarely supporting it for a little boost.

And the name of that killer app, using these DSP type features? Local AI.