You can still get a few phones with built-in headphones jacks. They tend to be lower-end and small.
I was just looking at phones with very long battery life yesterday, and I noticed that the phone currently at the top of the list I was looking at, a high-end, large, gaming phone, also had a headphones jack. The article also commented on how unusual that was.
That’s new and current. Midrange-and-up phones with audio jacks aren’t common, but they are out there.
Honestly, I’d just get a USB C audio interface with pass-through PD so that you can still charge with it plugged in and just leave that plugged into your headphones if you want to use 1/8th inch headphones. It’s slightly more to carry around, but not that much more.
Plus, the last smartphone I had with a built-in audio DAC would spill noise into the headphones output when charging. Very annoying. Needed better power circuitry. I don’t know if any given USB C audio interface avoids the issue, but if it’s built into the phone, there’s a limited amount you can do about it. If it’s external, you can swap it, and there’s the hope that their less-limited space constraints meant that they put in better power supply circuitry.