tagged template does not cause execution of given string. tagged template is just a function and in this case it's simply a proxy for console.log() which also doesn't cause execution of given string.

so how does it get executed?

unless it was just an example and you are supposed to switch in $ from some third party library... which is another dependency in addition to deno... and which can be shai-huluded anytime or you may be offline and cannot install it when you run the script?

Yes, it's another dependency (dax). The example with console.log is just that, an example. Standard dependency management practices apply, e.g. pinning a version/commit hash.