Not as easy as it once was. Security was beefed up with every iteration after iOS 10, in the hardware (post-iPhone X) and the software. 10 was the last good time of jailbreaking ease, where a jailbreak.me type of exploit was released. It’s pure luck now. Most talented developers have either left the scene due to ungrateful people, sadly, or joined Apple’s Bounty program. You can’t tell what version a brand-new boxed iPhone is on because Apple obfuscated the serial numbers. iOS 15 introduced SSV (Sealed System Volume) meaning no touching root, forcing a halt which was eventually solved with “rootless” jailbreaks. They made it harder to downgrade to a jailbreakable version due to SEP (Secure Enclave Processor), and Blobs are useless now because of cryptex1, introduced in iOS 16. This means no downgrades to unsigned firmwares at all except within patch versions (like 16.3 and 16.3.1). iOS 17 could be even worse, time will tell.