Who cares. Whether they have or not tells me nothing about the quality of support. You can have good third party support on a handheld (I.E. Square Enix and Atlus's support of the DS for example), or bad third party support on a console (I.E. the Wii U). In addition, the publishers being mentioned in the OP mostly focus on the home console games anyways. And they're western publishers. It would be like saying Bravely Default 2 is a sign that the Switch is a successor to the 3DS . It's not even that the base conclusion is wrong, it's just that the way you came to it is flawed.
I mean, you could easily just say the mobile shovelware which clogs the eshop makes the Switch more comparable to a portable, or even a phone, but you'd be stupid for saying that.
Yes, that's my point. Publishers who primarily ignore handhelds and focus on home consoles are publishing their home console games on the Switch.
As for Bravely Default 2, it's not uncommon for a release in a series to switch back and forth between handhelds and consoles. Luigi's Mansion went from Gamecube (home console) to Luigi's Mansion 2 on 3DS (handheld) back to Luigi's Mansion 3 on Nintendo Switch (hybrid). I'm not arguing that Nintendo treated the 3DS as a home console because they released the sequel of a home console game on it. And, all video game systems have shovelware as a fact of life. "Life of Black Tiger" is on both PS4 and mobile.