[AlotOfReading]

It's worth noting that effective population size != actual population size. The former is simply a lower bound on it. If the population is structured enough and in the right ways, the actual size can be orders of magnitude higher. This has been an issue with several supposed bottlenecks within African populations.

[davisYC]

the rule of thumb for mammals is Ne is 30% of census size.

i think this is probably an overestimate tbh (assumes poisson distribution of offspring).

[AlotOfReading]

I'm not sure that's super applicable to humans. Doesn't it also assume panmixia and non-overlapping generations?

Either way, my understanding is that all indications point to middle and late Pleistocene populations being highly structured and "unusual" as far as standard assumptions go.