Someone's got to actually implement the design, and if they're doing that well and at speed, they don't usually have time to absorb the full context of why, and that's okay.
Everyone has a role, not everyone needs to make strategy calls.
Sure, but it's easier to stay motivated and effectice in whatever role you have when you have enough context. And some roles are too small for some people as they develop in their careers.
I totally agree, however there are only 8 hours in a work day, and programmers need to understand that their 8 hours have to be focused on producing code, not on understanding the business, if the choice ever does come up (and it ought to).
Pretending like every single employee needs to have a complete view of the entire business is absurd, I hope that's not what you're suggesting.
Everyone has a role, not everyone needs to make strategy calls.