4chan

It won't fix it, but it can mitigate it to an extent.

Pets are a expense and a responsibility, with conversations being one sided, so their less than ideal for shut ins who struggle to function to begin with.

Therapy could help, but is also an expense and still has the barrier of a direct interpersonal interaction.

Both of these also have the issue of intimacy being non-existent. An AI offers a chance for low stakes, human like interaction that can be intimate.