Just to be clear, the “reason” here is that your expectations are not correctly aligned with the project goals.

I believe the other commenter was saying that initially Tesla’s only competition was lacking (“basically like the Leaf”), not saying that the Tesla product was.

Now that Tesla faces credible competition from other automakers, they face a much steeper challenge to retain their market share.

You are describing the GPL. FOSS encompasses many licenses in addition to the GPL and those other licenses do not fit your description above.