TIPS prices on the secondary market have decreased because the yields have gone up. If you hold to maturity and never plan to sell on the secondary market, this doesn't change what you can redeem them for at maturity. This is the same issue with nominal bonds and bond funds. Bond funds don't have a maturity date so you never know if your NAV is going to be more or less than your original purchase. In a rising rate environment, it is likely to be much less, as explained in this Forbes article -
https://www.early-retirement.org/forums/f28/bond-vs-bond-fund-114703-9.html#post2816309.
As Freedom56 has pointed out many times recently, bond funds introduce an element of market risk into products that normally have none. TIPS held to maturity have not lost money on a total return basis. That is simply not true. Older 2% TIPS have returned 10%. If you have a $10K car you bought from the government and they guarantee you they will buy it back for $10K plus inflation in 5 years, and someone offers you $8K plus inflation for it before the 5 years are up, you only lose money if you sell it for the $8K. But that would be stupid so most intelligent people would not do it, unless they were desperate for cash. Would you say you lost money on the car because the $8K offer existed? Even if you didn't plan to sell for $8K, but were going to stick to your original $10K offer?
Current TIPS yields are around 1% or
more over CPI inflation. This is something that can easily be looked up here -
United States Rates & Bonds - Bloomberg. TIPS real yields have recently been increasing, not decreasing, as you have posted. They currently have higher real yields than I bonds and no annual limits.