Why wouldn't one of the hundreds and probably thousands of companies that can make phones at scale not jump in? These are all pretty much off the shelf parts.

Why did Google even attempt Project Ara? Why did Fairphone or Teracube never produce a compelling product?

If anyone could make replaceable batteries work, even at a premium, it would be a big hit. I remember replaceable batteries and they were incredible. The batteries were slim, can barely feel them in your pocket. I popped 2 or 3 for my camping trip and never had to worry about charging.

The idea that there's collusion in one of the most competitive marketplaces in the world (consumer electronics) is an extraordinary claim. Companies don't just nuke their products and survive long term.