How many people does it take to remember everybody?

As we've seen, the hive has been able to not only remember with extreme precision the lives and memories of anybody who was once part of it, but it's capable of maintaining those memories even once those people are gone. This implies that the remaining population is storing or passing along somehow memories of people. But this raises an interesting question and a potential problem, will there come a point as their population has decreases so much that it will become difficult for the hive to remember everything and everyone? Or even, less stable?

We know that the hive does seem to have some sort of range limit. It doesn't appear to be immediately connected to the planet the RNA code came from. It does seem to be able to connect with people in outer space somehow, which to me does lead to questions about if the radio waves are how they're able to bypass total isolation. (It could very well have some connection to the signal the satellite picked up that started all this). So it's hard to say if their population got extremely small, how well they would be able to communicate on Earth without some sort of technological assistance.

Regardless though, I do think if their numbers do get very low, it could create problems for them after a certain point. Maybe they selectively forget things, maybe they become more emotionally unstable. At half the original population, everybody would have to remember two full lives. What will that look like when they're at a 6th, or 10th? Are the memories just scattered little by little amongst everybody? Or is a single individual responsible for it somehow? And does that mean when large amounts of the population dies, with it potentially dies a bunch of information if it was being stored among those individuals? I would assume yes.