You wouldn't have to be 80 and living at Bethel™. If you'd spent the majority of your life as a devout JW, with all your friendships and social activity JW centric, and you've treated non-JW or faded/DF'd/DA'd relatives like crap for decades, there's really no point in leaving the JWs and starting fresh.
You might be able to mend fences with the relatives you've ignored/snubbed all those years, but the risk of being expelled and losing the remainder of your social/support system would be overwhelmingly daunting.
I wouldn't want to be in their position. It was hard enough leaving in my 30s and starting fresh. I'd hate to be the one who came to the realization that I'd pissed my entire life away on a cult, one that lured me in, compelled me to alienate family and friends, induced me to give my hard earned money to them and made them billionaires while I denied myself the pleasures in life.
I daresay that many of the elderly JWs realize, on some level, that it's all a scam, and have figured out a way to pull back financial support of the whOrganization while using the Meetings™ and Field Service™ as a way to have their social needs met. At the same time, they try to keep relationships with former JWs in their family on the down-low, knowing that some day they may need their assistance.