As a (very) amateur photographer, this doesn’t make sense to me. Flashes indoors always look terrible in my experience, and modern smartphones are great in low light.
Modern smartphones perform very admirably in low light, but with some undesirable (IMO) tradeoffs: you get all kinds of weird artifacts from extrapolation, and the overall image frequently looks muddy compared to a low-light capture on a DSLR or mirrorless camera (which tend to look noisy instead). I do, however, regularly make those tradeoffs when I don't want to bug people with a flash or haul a full camera body to a show, though!
I think my use of flash indoors amounts to an aesthetic preference: I like the way skin tones come out on the combination of a ludicrous P&S flash and a "cheap" color stock like Gold 200. The tradeoff is glare and red-eye, both of which can be compensated for during compensation or with editing after the fact.
Using flash on color negative film is a very different experience from digital. Xenon flashes do really well with film, and don't blow out highlights like digital, giving a smooth rolloff that's very pleasing to the eye.
> modern smartphones are great in low light.
This is only true if you only view images on a smartphone. Blow them up on a 23 inch or larger monitor and you'll notice tons of digital NR, artifacting, and other fuckery where the image processing algorithms have tried to recover detail and not really done so all that well.
