I wrote jonesforth which is a simple threaded FORTH (in other words, interpreted and certainly not a modern FORTH). Threaded interpreters produce compact code. They are not efficient on modern CPUs, because they interact badly with branch prediction. For embedded cases where memory is at a premium and you usually have a simple CPU like an Arduino, FORTH is a great fit still.

Modern FORTHs are all compiled (as indeed are modern Javascripts). In my view FORTH is a pretty horrible language to write code in, and if you lose the advantage of the compact code for the embedded case then you might as well use a nice compiled language - whatever is your preference, but my preference would not be FORTH if I had to write code all day long in it.