3.5mm jack takes way to much space, and it requires a dedicated DAC circuit. And there is not enough users to warrant it anymore, especially considering the existance of usbc to 3.5mm adapters which do exactly the same without wasting internal space.
3.5mm is bound to disappear everywhere but dedicated audiophile hardware.
I’m a vinyl collector and audiophile myself, I’d love to see analogical staying relevant, but let’s be realistic, smartphones are not dedicated enough to music to waste space for a feature that only 10% of the user will ever need.
If you really need a portable device with a 3.5mm jack, go buy a Walkman. Sony still make new ones, and they all have 3.5mm jacks.