Generally 70 is the age at which it becomes problematic for insurers to approve pilots. The industry understanding is that pilots who were covered before they turned 70 will continue to be covered after they turn 70. Non-disclosure of age risks non-coverage!
When necessary and fisable True-Course sets up in-person meetings between the insured and the underwriter. This is an effective method to gain trust from the insurance company to continue flying well past 70. The assumption of course is that the pilot is in very good physical and mental health and the interaction in the meeting makes that clear.
The biggest challenge we see in our experience is letting go and hanging up your headset when it’s no longer 100% safe to fly in your condition. A transition consisting of flying dual with a younger pilot is always an option, but a lot of pilots prefer to pass on that.
Know your limitations and fly safe!