Generally speaking, there's a decent chance that they wouldn't be able to afford honoring the agreements. I would speculate that what would happen would be up to whatever regulatory body that oversees this. Most actuaries I've met consider life to stop no later than 120, and products reflects this.

You can compare the price of insuring against invalidity as e.g. a 30 year old with the price of a life annuity to see just how expensive it could be.