At least at the moment, it would seemingly make more sense to invest in 1-year treasury bonds. The interest rate is higher, they are more liquid, they are more convenient to buy and sell, and they are taxed the same as I-bonds.
There's also no limit to the amount you can buy.
And what are you going to do with that money in one year. If you’ll need to invest it again the answer is not so obvious.
https://treasurydirect.gov/indiv/research/indepth/ibonds/res...