Every holder of Bitcoin is paying, by having their coins depreciate 10% each year, perpetually, due to the cost of PoW mining. Though we have been lucky so far, since the inflow of capital far outpaces this depreciation in the past. But at some point, the inflow of capital will be unable to keep up, and we will see the depreciation, we are possibly seeing it right now.
You are confusing inflation with price appreciation, and your claim is based entirely on a timeframe that you selected to fit your bias.
Just as easily, you could say that Bitcoin price has appreciated by greater than 4x per year and be equally correct.
There is inflation in the money supply of Bitcoin, which was and is known (since it wasn't heavily pre-mined like other coins), math-based, predictable, and
FALLING over time. Because industrial miners are profit-focused, they are selling virtually immediately to lock-in current price to pay the bills, rather than speculating about future value. This causes somewhere between 0 and 3600 BTC to be sold daily onto the market, creating natural downward pressure on price.