Marketing is all about tease and seduction. Most consumers will get a small taste, become intrigued, and then scour the web looking for more information like advance reviews. Why spend a ton of time on creative when most potential buyers are going to base their decision mostly off of a YouTube review. Your browser data will then be used to target you with secondary advertising with a call to action (BUY NOW @ ___________!!!) soon thereafter.
Product line decisions like drops and updates? Those are made for a myriad of reasons. Most often, sales will dictate what stays and what goes. Models like the Streak and Pegasus Turbo don't sell in great numbers compared to more standard models. They are niche shoes with a very low reward customer when compared to more standard models. Personally, I am rather surprised that the Streak Series lasted as long as it did. I speculate that the Peg Turbo was meant as a fast day companion for the standard Pegasus but became obsolete with more plated options being available. Most "serious" runners have a trainer and a racer. If you own a Peg 37 (or Zoom Fly 3) and a Next %, then you likely won't shell out another $180 for a non-plated tempo day shoe.
Footwear also operates much like the auto industry but with faster line turnovers. Today's foam/plate/silhouette/color/gimmick will be supplanted by another manufacturer's foam/plate/etc. within six months. That makes your current product "old" and banished to the clearance section at retail. Right now, there is an arms race going on because everyone wants the latest and greatest technology. I am sympathetic with runners that want a consistent fit and feel but, store buyers, influencers, and online reviewers will shun "old" stuff and it suffers sales losses. It is confusing but, right or wrong, the footwear companies feel the need to constantly keep things fresh. Remember adidas Boost? Five years ago, it was the sh**! Then Nike dropped Zoom X and Boost felt heavy and slow. Hoka did a carbon plate first, then Nike's carbon plate was stiffer, faster, and setting records. Now everyone is forced to do plated shoes to stay relevant. The North Face is doing plated TRAIL shoes now. When all is said and done, the big manufacturers will sell more units of "new" models than they will see second purchases of "old" favorites.
Someone mentioned that they can't find adidas Boston 9 and Adios models any longer. I understand that they are re-working all of their lightweight performance shoes to feature Lightstrike and either carbon plates/energy rods for 2021. I have seen the Boston 10 prototype and it is now a racing shoe with energy rods like the Adizero Adios Pro.
All change, all the time is the game now. Athletic footwear sales are up and Wall Street likes those numbers. Don't expect that to change in the near term.