"This new tool allows for writing all this code ..... but every person and company, in unison, in a grand conspiracy, all decided to only write private software with it that they aren't releasing to the public in any way"
Seems reasonable
Seems reasonable
We could try steelmaning this argument instead: it's enough that most big companies who would otherwise have incentives to contribute.
Before FOSS got in fashion, around the early 2000s, most commercial companies wouldn't touch it as contributors and were openly avert to it, and to open sourcing their stuff. This can be the case again.
People are shamed for using LLMs at all. So they use them privately, hide them, or disguise their use.
They are definitely being used for public projects. But people are afraid of backlash. Look at some of the comments here.
Hell, Reddit is extraordinarily against LLMs such that even neutral takes are down voted. Mostly by younger generations that aren't in the workforce.
Then you have all the regular people against AI generally.
Ironically there is a conspiracy here. But in the opposite direction.