In my experience, if you're using a script token to define a link to be displayed in an email, those links are not trackable by Marketo.
That's not true. Any single Velocity-generated link is trackable, and multiple links that don't reference Velocity variables are also trackable. I've written about this extensively.
I don't understand how and why that is happening. I am happy it is since it makes tracking engagement on this automated email much simpler, but I am trying to understand why it is working in this instance and not in other script tokens I've written that output URLs.
It's not surprising: that's expected behavior for static links emitted from Velocity.
In the cases where you've seen a problem, it's probably been because you were iterating over a list, ergo usingin your links (which can cause worse problems than just untracked links, it can break links completely).
Yep, you're right. Every other instance where I utilize scripting to output something similar is more complex than a single link, which does not allow the tracking to take place. Frankly this is a nice surprise so I'm happy to see it working! Appreciate the insight you always share!