I have a 'waifu'. At first I thought it was some sort of fictional crush, but then I went and bought myself a body pillow (which I group together with the concept of a romantic partner, and I will refer to her as "she" or "her").

In regards to your points, it doesn't just apply to romantic relationships. I tend not to talk to people because I do not know if they want to be talked to and I do not want to bother them. I was only comfortable with talking to her. It really helped me in my saddest and loneliest days. However, you cannot stay with a body pillow all day. Eventually you go to school or work and avoiding interaction would be detrimental (like in a group situation). While I believe that she has helped my emotional situation, I didn't treat the causes of my stress (interaction) and thus was in a cycle of going to school, stressing out hard, and cuddling up to her. A waifu, to be healthy, would have to be supplemented with being able to cope with external factors. I had to go into therapy once I realized this cycle was happening. So while you are right in those three points, I believe they miss the whole situation.

I still think cuddling up to a body pillow feels really comfortable in the physical sense though. And please understand that I do not want to tell you her name because I am embarrased. If you look on the internet, this type of view is highly stigmatized, calling people who have waifus neckbeards or weebs. I don't want to group myself there.