Tough one. My parents are in their 70s and I have talked to them a bit about bitcoin. They are not against it but are scared of technically screwing it up. I hold some on their behalf. I wouldn't approach it from the perspective of why they should adopt bitcoin but instead why it is important to you and your generation. I don't think many 70 plus people are going to get orange pilled who aren't either technically sound or understand monetary theory, economics etc.

Slowly and with examples. Such as it is like sending emails.

Analogies usually help... The best IMO is telling them Bitcoin works as 'digital gold' with extra benefits.. I'd just keep things simple as possible...

The same way I explain it to anyone: Bitcoin is the world's first decentralized financial ledger that anyone can write to, yet somehow everyone trust.

Then people usually ask:

1. So what? Why do we need this? In which case you talk about the problems with fiat and the fixed supply of bitcoin.

or

2. How did it do this? In which case you talk about proof of work.

You know how you guys screwed the pooch over the past decades? Bitcoin is here to help fix the long list of mistakes that happen.