I think the person asking the question wasn't looking at Macs due to a cost issue, not necessarily because of iOS
Actually he was not ruling out Macs, nor Windows "I have no preference between open- and closed-source software as an end-user; I just care about the quality of the product."
also "I'm more than willing to do, but I'm not so sure I want Windows 8 and I'm just not sure I can afford to go with a Mac on top of the $600 for Finale."
From what i have just checked you can get a refurbished Macbook Air for 849$ in Canada, add 200$ for Logic and while this is not a bargain laptop it is a decent price for the most portable DAW. He can also get a used Macbook Air or Pro for a lot less.
In music production the laptop is probably not the most expensive equipment: synths, mics, mixers, audio interfaces can all go from a few hundreds to a few grands when you add them all together to get a basic setup.