I Googled it, and the results were about evenly split on whether "et al."
primarily stands for "et alii" (masculine) or "et alia" (neuter). But they agree that it can stand for either of those, as well as "et aliae" (feminine). In Latin, neuter nouns don't generally refer to people, so whether neuter is supposedly the primary meaning or just an option, it seems to mandate that the phrase can be used for things. On the other hand, the converse isn't true: neuter nouns don't refer to people, but masculine and feminine nouns frequently refer to things. In fact, the neuter gender only accounts for a relatively small fraction of Latin nouns. Thus, even "et alii" or "et aliae" would often be the correct choice in Latin for lists of things, depending on the type of thing. (Of course, there's no Latin word for "compiler", so there's no way to say which would be most appropriate in this particular case, unless you refer to the Vatican's book of Latin neologisms or something.) The word itself just means "other", with nothing inherently limiting it to describing people. In English, substantive adjectives (adjectives without nouns) do tend to default to people unless a noun has been specified: thus it's natural to say "compilers including Clang, GCC, and others", but not just "Clang, GCC, and others". But Latin likes to use substantive adjectives much more liberally. Especially in the neuter, I'm pretty sure "alia" is perfectly good by itself where in English you'd need to say "other things".
Anyway, you could argue that the use of "et al." in English has a restriction that doesn't come from the original Latin. Many of the Google results I found do claim that there's a convention of using "etc." for things and "et al." for people, although that seems to conflict with the idea that "et al." primarily stands for "et alia". But they mostly don't claim that that convention is a hard rule. And I don't think it makes much sense to establish one, considering the original meaning.
[edit: reworded for clarity]