the article explain the downside of putting in IRA is that the Bitcoin will have to be sold in order to use it once you reach retirement age as well as penalties if sold earlier. It recommends hodling yourself and borrowing against your stack.

A combination of both strategies, IRA and your own stack is likely the best way to go. I must say IMO confiscation is the larger risk facing IRAs, they are centralized and when BTC moons and govs go broke, they will be targeted. So save there accordantly.