Getting "building something no one wants" vibes from the AI girlfriend startups. I don't think men are going to drop out of the dating market until we have some kind of robotics/social revolution, possibly post-AGI. Lonely dudes are just not that interested in talking to chatbots that (so they believe) lack any kind of internal emotion or psychological life, cannot be shown to their friends/parents, and cannot have sex or bear children.
I agree: the capabilities of AI romantic partners probably aren't the bottleneck to their wider adoption, considering the success of relatively primitive chatbots like Replika at attracting users. People sometimes become romantically attached to non-AI anime/video game characters despite not being able to interact with them at all! There doesn't appear to be much correlation between the interactive capabilities of fictional-character romantic partners and their appeal to users/followers.
There's a parallel here with VR. Some part of peoples' intuition says that VR porn/video games has to be a Next Evolution over simple screen + keyboard interfaces, worth pouring billions of dollars into, because VR is "more immersive" or something. But actually a laptop and a USB mouse works just fine.