It’s not normal. That same support article states a fresh iPhone 7 would last 9 days. That’s less than half a percent every hour. 3-4% over an 8 hour period but I’d expect much less than that. Batteries and the way iPhones consume their power have been become more efficient since 2016.

I can also confidently say I’ve never seen what I would consider to be excessive battery drain on any iPhone I’ve ever had without some sort of software issue behind it.

Found an article of someone who made their iPhone 5 survive nearly a week between charges (with some pretty unrealistic usage) which has to suggest the battery was using pretty much nothing in standby time. iPhones have always been legendary for standby time, like I said above