You are correct: 1985 vs 1991. My bad. I just heard about AIM at the time, whereas ARM was relatively unknown (well, at least to me ;) until the rise of mobile.

Edit: It’s a bit confusing because ARM the architecture is older than ARM the company. But yes, both precede AIM/PowerPC.

My main point was that mobile made RISC ubiquitous.

If you consider the evolution IBM 801 -> ROMP -> POWER -> PowerPC then you might say the that the roots of the PowerPC are from 1975, or 1982, or 1990 or 1991 and you would have a valid point in all cases.

But it is very reasonable to consider ARM older than PowerPC.