So yeah, they break, but they are (or used to be?) quite cheap to fix (and this was one of the super thin 13" xps)
I had a slim XPS13 and IIRC the headphone jack was on it's own little board. That makes it quick/easy/cheap to repair if you know what you're doing / have the service manual / are comfortable taking it apart.
Not all things are designed that way; sometimes the jack is right on the main board and most people that buy dell laptops are not going to DIY through ali express; they're going to use up phone support time, require a shipping label, technician time ... etc.
You take care of your hardware, even during "heavy use," many people absolutely do not - and are downright abusive.
Many of these parts exhibit partial or intermittent failure modes where it's more expensive and difficult to determine warranty eligibility than to just fix the problem. Peanut butter in the jack, loose solder joints, whatever.
Doesn't this make including the jack even less justifiable?