The sad part is that you assume that modern day billboards aren't tracking you. All you need is a camera, a tiny computer and some AI. Once walked by a fully electronic billboard where the slideshow crashed, the log it displayed listed everything it could identify about people passing by, age, gender, height, hair color, emotional state, ... .
Is JS synonymous with tracking? Why can't you just track server side? I don't see how removing JS from ads would prevent FB from targeting me on my FB feed.
The ads market is a very complex and competitive industry. This means that practically every display side provider has their own special "ad product" to differentiate themselves. Almost all of these require JavaScript to implement their key features.
In addition there could be 4 or even more parties involved in showing an ad (publisher, publisher's supply side provider, advertiser's display side provider, advertiser, plus miscellaneous middlemen). These different parties may not trust each other, so they currently use JavaScript to send (via `fetch`) themselves information about the auction to check up on each other.
But ... the ad industry would never accept a static ad more akin to a billboard than a tracking device. Many times in the past malware has found its way into networks run by the more highly regarded ad systems.
https://en.wikipedia.org/wiki/Malvertising
If a content publisher refuses to let people read articles without a subscription or with an ad blocker, I am ok with that. It is their choice.