The point is that SOMEONE is sitting there with a 3% investment that is basically paying a negative interest rate when you account for inflation. And they’re stuck with it for the next 30 years if I live long enough to see the end of it and I don’t move.
That is not a hedging technique by definition. If you dont own the “thing”, you are out, there is no risk to hedge.
Plus you are confusing monetary inflation with demand/supply price increases. Investors focus on mainly the former when loaning money “If I loan X number of dollars, what will those dollars be worth when I am repaid”.
Your 8% inflation is today. Bond holders forecast what it will be over a 20 or 30 year bond period. Does a startup business base a 20 year business plan on what the P&L will be in year one? No of course not.