system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: If our brains have limited storage capacity, what happens when we max it out?

Do we start erasing old memories, or simply stop storing new information?

This is a hypotethical question, but if humans had longer lifetimes, would that mean that we would hit a plateu in the way we store information and we would stop being subsceptible to new information, in turn turning older people useless for scientific progression.
gpt
You start forgetting the information you never use, for example a phone number from your second cousin that was used 12 years ago.
The probability of it ever happening in a lifetime is fairly low due as we have a large capacity to retain information.