Prep method matters so much though. For comparison, a standard double shot of espresso is typically 18g of coffee. This would yield approximately 110mg of caffeine.
By comparison, the same 18g brewed using a pour over method should yield an 8oz cup of coffee with … likely around 170mg of caffeine.
Check out this James Hoffmann video specifically on this topic: https://youtube.com/watch?v=etnMr8oUSDo