I understand where you're both coming from, I just honestly don't think Lite is really a more "casual" device than the base Switch, it's niche is more Japan, parents wanting a more durable and affordable system for their kids, and 3DS owners who haven't upgraded yet cos they saw the base model as too expensive and not portable enough.
If anything, it's the base system that's more casual-friendly as its more of a trendy multipurpose device as opposed the Lite which more resembles a traditional dedicated gaming handheld. I don't think the price difference is any real obstacle to a consumer in this age of phones and tablets costing far more.
I worked gaming retail for a while. A hundred dollars in a gaming system makes a huge difference. The points you made are understandable, but price overrides them. Someone on the fence for the Switch who has fond memories of brain age and wii fit would be far more likely to make an impulse purchase at the 199 price point.