In the example above, I believe that's the case. Again, an issue with switching between projects/styles, for me - one client/project insists on "const" in JS.

In the example above, I believe that's the case. Again, an issue with switching between projects/styles, for me - one client/project insists on "const" in JS. Another client/project is supporting a product on IE9 for a client of theirs, but doesn't use any build tool for some of that JS, so we're not even supposed to use "let" or anything else "new" for some of that project. Mentally switching between those two worlds is like jumping between 2019 and 2009 every few days. Realistically, could we introduce a transpiler? Technically yes, but operationally? It's a Frankenstein project that has so many larger issues that's low on the list for people (sections of the functionality are being migrated over to react altogether, and throwing 'more tools' in to the mix on legacy stuff is not desired).