There’s a famous quote from him about success and product focus, and it seems pretty obvious that first they tried using Ive as a product guy substitute (or put him forward as one), then they gave up entirely.
Steve used his own stuff and didn’t hesitate to demand it meet his quality expectations… but I genuinely can’t imagine Tim Cook deciding on a feature without a spreadsheet weighing pros and cons against surveys of user feedback statistics and the entire development time planned out Waterfall style… even if that’s just “these buttons suck and are confusing, use better ones”, he’d still in my little imagination scenario, be scrutinising the spreadsheet on an iPad and deciding that the fix isn’t valuable enough.