It's also less pressure, a more comfortable environment (home vs. stranger's office), no commitments to a next session, and less embarrassing (sharing your personal issues to a computer via text is less anxiety-inducing than saying them to a person's face).
With that all said, I'm strongly opposed to people using LLMs as therapists.
In their mind, most of the times, if there is no one standing behind them when they chat with a LLM, then the conversation for most intents and purposes is private.
Obviously, us who are born with a keyboard in front of our hands, know this to not be true, and know we're being tracked constantly with our data being sold to the highest bidder. But the typical person have more or less zero concerns about this, which is why it's not a priority issue to be solved.
I haven't been so unlucky myself, but I know many who've had terrible first experiences with therapists and psychologists, where I'm wondering why those people even are in the job they are, but some of them got so turned off they stopped trying to find anyone else to help them, because they think most mental health professionals would be the same as the first person they sought help from.
However, unless we have a measure on how helpful self-help books actually are, we still don't know if they help or not.
Should be banned. Average people have no basis to know whether drug X is appropriate for them. If your doctor thinks you need it, he'll tell you. These ads also perpetuate the harmful idea that there's a pill for everything.