I Bonds make sense right now, but you are limited to $10k per year. So, I don’t view it as a big decision. If you are close to FIRE, they aren’t going to make up a significant portion of your total amount invested.
I wouldn’t sweat any decisions until you are talking about 10% or more of your total amount invested.
If you are early enough in the process that $10k is a significant percentage, then focusing on total spending and savings rates and developing good habits is more important than allocation decisions.
For the record, I’ll probably buy more I Bonds next year, as part of my total bond amount.