Inflation means tomorrow’s money is worth less; it impacts cashflows more when they are further out.

When the cost of money is near-zero, today’s values of near and distant cashflows are similar. When the cost is high, they are very different.

I’m not sure if you mean in your question that a project shown to track inflation will be unaffected. This is somewhat true — we see this in inflation-adjusted bonds etc. But inflation is far from a uniform effect, and I’ve never seen a pitch include inflation in its estimates…