You absolutely do NOT need multiple years of CS undergrad to have a sense for scalability. If you open your mind, you will see that world history is chock full of systems that have scaled -- they just don't happen to be written in binary or backed by CS degrees. And I would say that these historical systems share more similarities than you would think with scalable computer systems.
In order to be good at this kind of thing, one just needs some sense for abstract thinking -- which countless non-programmers have, we are actually not unique in that regard -- and if you are adequately dedicated, a few weeks (or a few months at most) of study time to understand fundamental algos and data structures. After one has an understanding of it, it will certainly take more time to become practically comfortable using said concepts, but that's what entry level jobs are for.