I don't accept the unregulated and uncontrolled use of LLMs for therapy for the same reason I don't accept arguments like "We should deregulate food safety because it means more food at lower cost to consumers" or "We should waive minimum space standards for permitted developments on existing buildings because it means more housing." We could "solve" the homeless problem tomorrow simply by building tenements (that is why they existed in the first place after all).

The harm LLMs do in this case is attested both by that NYT article and the more rigorous study from Stanford. There are two problems with your argument as I see it: 1. You're assuming "LLM therapy" is less harmful than "no therapy", an assumption I don't believe has been demonstrated. 2. You're not taking into account the long term harm of putting in place a solution that's "not fit for human use" as in the housing and food examples: once these things become accepted, they form the baseline of the new accepted "minimum standard of living", bringing that standard down for everyone.

You claim to be making a utilitarian as opposed to a nonmaleficent argument, but, for the reasons I've stated here, I don't believe it's a utilitarian argument at all.