No, one doesn't. Tim Cook has stated exactly why they haven't gone down that path yet. The only reason other manufacturers went bigger earlier is because of the poorer power efficiency of their hardware and software.
I disagree - there's nothing that -compels- PC manufacturers to support VGA directly on their hardware. You don't need to replace working projectors, simply support them via adapters. In turn this would push projector manufacturers into using more modern connector technology.