A lot of people want a camera that's just a camera and a phone that's just a phone, without all that smartphone nonsense (not me, I'm well up for technology)
It's not sensors that give you image quality, it's optics; you need to get as much light as possible onto the sensor which you simply...
"low end digital cameras" - your man is talking bollocks on this one. I have a 2007 vintage Sony camera that has superior optics and a better flash than my smartphone. I would confidently predict that a sub £100 camera of today will outperform a smartphone in 5 years.