Yes, the pool is not always large enough, so you can throw it into a reinsurer from the insurance company. Yes, the reinsurance pool isn't always large enough, so you can retrocede to a few other reinsurers for diversification.

That pool isn't aways large enough, so you can securitise away the tail risks and aggregate loss risks into a cat bond, or a pandemic bond, or a longevity swap, or something fun.

These will then in turn be bought up by pension companies, in order to diversify against their market risks, and the needle returns to the start of the song, and we all sing along like before.