GNU Make does support multiple outputs, but the feature is very new (it's in the latest release that came out earlier this year), so if you didn't happen to catch that release announcement you probably missed it. The support is called 'grouped targets', documented in the second half of this page: https://www.gnu.org/software/make/manual/html_node/Multiple-... -- the syntax has &: in the rule line.

(One point you don't mention in your list of reasons why Make is successful is that it's reliably available everywhere. For projects that ship as source for others to build, that matters, and it delays uptake of fancy new build systems in that segment.)