The primary differences are 1. proper finger position and technique (mind your Ps and Qs); 2. better touch typing accuracy (see 1). Speed is probably roughly the same but with less backspacing. The staggered layout is weird; it's not natural at all and requires bizarre finger contortions designed to prevent mechanical typewriters from jamming. Ortholinear allows your fingers to move in perfectly straight lines, so it becomes incredibly easy to know exactly where a key should be without looking (honestly, can you type *$(@ without looking at your fingers?). Since we don't live in the 1890s, I think it's time to move on.

The biggest benefit is not exclusive to ortho, but fully programmable layouts have totally transformed the way I interact with the computer; I map space and enter to where my thumbs naturally rest, have momentary layer toggles on row four that allow me to type any shifted symbol from the home row (also numpad centered on jkl and arrows mapped to hjkl), and esc/ctrl on R3 C1 (caps lock). Most of the time I never move my fingers more than 1u from their home positions. In my experience ortholinear is easier to map since things like number pads are awkward on a staggered layout, and ortho R4 gives you the ability to toggle between six layers without moving your thumbs. I've arrived at such an efficient layout that I don't even use R1 and most of R4 at all.

Edit: you don't lose your ability to use a standard keyboard layout after learning ortho; it just feels like trading in your ferrari for a ford pinto.