Z stack strength and rigidity is a huge driver because it reduces charge back. Margins are super tight for a lot of OEMs and the PMs eliminate any non-profit features.

Off the top of my head, there are savings in: Pick and place Stack Assembly Testing Improved phones/hour and therefore shorter/cheaper factory runs Packaging, especially if you eliminate the shitty wired earpieces in the box Less weight/volume and cheaper shipping Reduced warranty / chargeback because things that don’t exist can’t fail

All of these savings are small. But remember that the goal is to make/sell 500K+ units. And, this is an industry where the bean counters will kill their mothers to shave a penny off of the BOM.

So, yeah, for the OEM eliminating headphone jacks is a complete no brainer.