1. If you are in poor health when the time comes to decide, no.
2. If you are in reasonably good health or better, maybe. It's simply a question of how much assured lifetime income you want to have. It's the best Singapore dollar lifetime annuity available anywhere, so you don't even have to think about which Singapore dollar annuity. That's the best one. All you have to decide is how much monthly income you want to have.
People trying to compare non-sovereign and non-life income streams are really leading you astray, in my view. A sovereign's lifetime assured income payout is VERY different than anything else.
With the good health assumption, personally I expect I'll start CPF LIFE annuity payments at age 70 (i.e. defer as long as possible) and with the 2% annual increase option (for an approximation of inflation adjustments, and to "backload" the payment stream).