Periodically, the suggestion is made. The latest similar argument - though he does not, in fact, take Apple’s name in vain - comes from Jeremiah Foster in the form of an open letter to Mark Shuttleworth, of Canonical/Ubuntu fame (oh yeah, and Soyuz).
The missive makes the same case I’ve seen and heard elsewhere, though certainly not in this direct a form. Distilled down, the argument runs as follows:
1. Supporting an operating system on all hardware platforms is hard
2. Supporting an operating system on one platform is easy (relatively speaking)
3. Proponents of desktop Linux, therefore, should do the latter (though obviously not at the expense of the former)