Performance has not hit a wall at all. More transistors was never going to speed up serial processes forever. Transistor count is still increasing, core count

Performance has not hit a wall at all. More transistors was never going to speed up serial processes forever. Transistor count is still increasing, core count is still increasing and software speed usually has room for a 10x-100x speedup in most places since it is usually done so poorly. Most of the time high end games are the only areas where CPUs are actually used to their potential because of memory latency.