I have to change an old ERP system (typical private admin site) interface to be more modern and responsive. I’m not a designer but a developer with some frontend experience so my plan was to buy a responsive template from Envato or other sources.
However as I see almost all admin templates use bootstrap and a mobile-first approach. Maybe I missed something, but for me it makes no sense to optimize an admin page for a phone screen. Instead, I would like to see optimizations for larger screens. Bootstrap media queries ends at 1200 px, but our customer uses displays that are at least 1366 px wide, the most being 1920 px wide and some even bigger screens like 2560 px. In rare cases, there are full HD tablets.
The mismatch between what I want and what is offered makes me wonder: Is there a good reason that large templates are not sold? Am I missing something that makes it a bad idea to optimize for these larger resolutions instead of 480 px and 768 px?