That’s a no brainer. Some years ago we only had like 3 or 4 different screen sizes, now you can view websites on a toaster. Welcome to the future. You get my point. It’s no longer enough to have a beautiful layout that works perfect on your own prefered devices. We have to create seamless layouts that work on any imaginable device. Or at least on those we expect your visitors to use. The trade-off being to pass on having a perfect layout or the cutting-edge user interaction features.
Of course it’s possbile to optimize in every direction but you know, that results in some overtime hours that need to be paid, too. To some up: Everything is possible, but at first we need to focus on presenting our content to as many users as possible in a nice and smooth way.