To say that the bond market "reflects current interest conditions" is like saying the stock market reflects current stock prices.
A dollar today is not the same as a dollar a year from now, which is also not the same as a dollar two years from now, and thus they have different prices.
I don't disagree with your conclusion. This is a technique for matching asset & liability timing (not really a market strategy), more suited to the corporate treasury than the retail investor.
Re: fees depends on your platform. Fidelity charges no fees or markups for treasuries but if your platform does it's something to consider in addition to bid/ask spread.
If you look at past data there is on average no difference between buying 1 year bonds and keeping them to maturity and buying 3 year bonds and selling after 1 year.
The only case maybe for buying 1 year bonds is where you have another contract which matures in 1 year denominated in the same currency. E.g. I have a mortgage payment of $1020 that I have to make in 1 year so I should invest $1000 into a bond that pays 2% interest.
Can you link that data? Is it data from the past 5-10 years? Or much more historical?
Not quite. Commissions are charged on equities. Markups are charged on bonds. Markups are the difference between what the broker paid and how much a retail investor has to pay the broker and are much more opaque. They can be quite hefty. One just doesn't notice.