"If I'm going to keep my computer for five years, six years, seven years, I'm going to get a Mac," Gottheil said of a hypothetical consumer's reasoning.
The Mac also plays a part in Apple's larger strategy, Cook said in his defense of the line, citing the familiar "halo" effect.
"We believe that if anything the huge growth in tablets may wind up benefiting the Mac, because it pushes people to think about the product they're buying in a different manner," said Cook Tuesday. "People may be even more willing to buy a Mac, where today they may be buying a PC."
Gottheil agreed. "The Mac remains a good, solid business, and it contributes to their other businesses," he said.
Apple also sold 19.5 million iPads in the first quarter, a 65% year-over-year increase.
When iPad and Mac unit sales are combined -- an approach many analysts are advocating because tablets have assumed some of the tasks once relegated to personal computers -- Apple posted year-over-year sales of 23.4 million units, a jump of 48% compared to 2012.
If iPads were considered equivalent to PCs, Apple's 23.4 million combined sales last quarter would have pushed the company into the top spot worldwide, with sales twice those of either Hewlett-Packard or Lenovo, the No. 1 and No. 2 OEMs in Gartner's and IDC's rankings.
HP shipped few tablets last quarter; Lenovo claimed it sold approximately 800,000 tablets in the fourth quarter of 2012, its most recently-reported period.
The Mac accounted for 13% of Apple's total revenue of $43.6 billion in the quarter ending March 30, up a few points from the previous period. (Data: Apple.)
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