Given that generation gains are not sufficient to make a Max twice as fast as the previous-gen Ultra, a longer cycle is rational. The M3 Ultra is still the fastest M-series system.
M3 Ultra, 3.3k single core 27k multicore on Geekbench. https://browser.geekbench.com/v6/cpu/16959045
M5 Max, 4.3k single core 29k multicore https://browser.geekbench.com/v6/cpu/16956481