At a simplistic level, the difference between RISC and CISC processor design boils down to having many registers and reduced instructions, or few registers and extra specialized instructions.

What was being described is going to programming from a RISC-like design processor to a CISC-like design processor, and how they felt constrained after doing so. It likely does feel more constraining (I don't really remember how I felt about it back when I did it, but I also went the other direction, and only in the context of classwork), but in the end, most people are programming a level removed from that anyways.

There used to be quite a lot of arguments about what design was better (IMO mostly fueled by Macs running a RISC processor and Windows running a CISC processor, at least until Apple switched to x86). I find it slightly comical that both designs ended up in a fairly similar place though (with RISC processors adding extra instructions, and CISC processors adding more registers, even if mostly just logical registers).