It's mostly bias from a few people like Nagoshi, Harada and Kondo. According to Harada's logic a Switch release for the higher-budget Bandai Namco Studios titles would make them lose their appeal as premium products because the Switch is a "kiddy console", so while only PS gets those, Switch gets the (often very low effort) kiddy games. It almost feels like he's trying to make his fantasy come true (PS = hardcore gamers / Nintendo = kids). Sooner or later he and Nagoshi will have to realize that the Switch's success is not just from more kids and casual gamers buying Nintendo hardware/software than before: all the players that PlayStation is losing in Japan haven't abandoned console gaming as a whole, most of them are moving to Switch and that trend is not going to stop anytime soon.
I don't have any hope for Kondo ever releasing a game on a non-Sony console/handheld, even when The Legend of Heroes and Ys decline even further every year.