Yeah, no fear involved at all, it's just something he just started doing lately, like maybe a couple weeks ago.
I know he likes his favorite corner in my room (even with that big bed - not that he doesn't enjoy the big bed!) and I figured that was why (den/enclosed area).
In fact, it was more the other way - he avoided walking/sitting/laying under the table for years. Now, he's just up and doing it LOL.