I think it's assumed that all CPUs for gaming, going forward, will have some form of hyperthreading. In any case, the discussion here is likely to assume "8 cores" only, since we had the 11700K and I have seen people on various forums actually recommend that over a 5600X to people purely because "8 cores".
But again, not 100% sure, and altho the above scenario of 8c8t vs 8c16t sure applies, based on the CPUs Steve is talking about, that seems a fair assumption to make (that multithreading is a given). In any case, multithreading, in its current form of dual threading, is bound to be better than a non multi threaded CPU with same no of cores, but this will, as mentioned in the video, depend on many other factors such as architecture's efficiency and power, core count, thread count.
Th thread count argument might become even more complicated in the future, with the advent of quad threading. But whatever happens, the future does look exciting!