Disclaimer: I'm not an Apple user, but I'm a an avid listener and work in music industry. Unfortunately there's a bunch of "killer apps" for musicians which have no alternative for Android. It's a pity there's no escape from the walled gardens.
But still less than a batter life of a phone. Running out of juice on them after a while become like a constant self-inflicting anxiety attack, with semi permanent jumps between "Should I plug them now in case I have to have it later" and "I like this song/track/mix, I will listen to it". IMHO, YMMV
Our Mini-Van also doesn't have BT. I have to use my USB-C adapter which means I can't charge and listen at the same time. Very inconvenient on long trips when I'm also using the phone for navigation.
I have several pairs of Bluetooth headphones but still use the 3.5mm jack on my SE all the time, and I use a 3.5mm lightning adapter with my iPad Pro.
I have bluetooth headphones, but I still rely on my wired earbuds if I go running, or if I want to travel light, or for phone calls. And I also have regular non-bluetooth good quality headphones that I like to use (especially when the bluetooth ones run out of battery). For me, it's not only a matter of sound quality, but I find it convenient to be able to plug any headphones without bothering with bluetooth.
There is no consumer device used by virtually everyone where every square millimeter counts more than in a cell phone. It's not like there's just an empty hole where the jack would be otherwise.
That space is being used for whatever component(s) Apple thinks its customers, as a whole, find more valuable -- i.e. a net increase in functionality for the average consumer, even if not for you personally.
This is assuming that "what Apple thinks its customers want" === "what Apples customers want"
That said, small but very decent DACs have been around for a while. There's one smaller than your pinky nail inside the lightning-to-3.5mm adapter included with newer iPhones.
There are plenty of good reasons to want a 3.5mm headphone jack on a phone. But audio quality is not one of them.
In response there are many that purchase media players with DACs for this specific reason. When 3.5mm jacks started getting removed measurements also turned to the DACs within usb c/lightning to 3.5mm cables.
