I don't know what the iMacs are like, but the Macbooks have gotten pretty good anti-reflective coating, and they have pretty bright backlight. I prefer my glossy 2015 Macbook Pro to my anti-glare matte 2009 Macbook Pro, even in difficult lighting.
If you're not used to it that can be jarring, but over time it's less of an issue.
It's not something I notice unless I'm in a really bad spot and there's tons of light coming in. Good thing civilization invented this thing called blinds.