Sure, we can only make guesses about general profitability within SCE WWS, although for the current situation it would be more useful to know what the ratio's been like in the last couple of years. Apart from them acquiring Media Molecule two years ago, I believe the most news in that period have been about studio closures, restructures and the loss of staff.
I guess it depends what you're paying attention to. In that period they also acquired Sucker Punch and expanded Naughty Dog to a two-team studio. Both SCEE and SCEA have also been hiring so I think job losses may well be more a case of rearranging resources vs large net losses to the headcount.
Anyway, back to the original point - we have zero visibility on individual studio profitability (asides from Media Molecule which was reportedly profitable last year revealed by an individual company filing they made in the UK). And I think it's tricky territory defending an assumption about them being 'mostly unprofitable' based on selective highlighting of stories. I would say the overall picture is one of continued strong commitment to first party development. Which isn't to say there aren't drawbacks - of course there are.