i think theres something to that. i saw some chinese here complaining in a hot pot restaurant that it wasn’t spicy enough. even tho it was totally spicy enough for most peoples tastes, but over there they eat those 100 chilli dishes so yea its not surprising their tastebuds can’t appriciate a normal amount any more.
In theory it doesn’t really taste of anything. It’s weird. It’s a component of familiar natural flavours, but there isn’t any food (AFAIK) that has a flavour that’s only or predominantly defined by umami. MSG is described as a “flavour enhancer” because that’s exactly what it is.
Sure, but there are certain foods whose taste is dominated by sweet, sour, bitter, or salt. You can say “saltiness” tastes like, uh, pure salt.
There’s a lot of recent debate over what counts as a ‘basic flavour’. Apparently there’s something about fat, in and of itself, that works a bit like MSG on our sense of taste - which presumably is why low-fat food has never really taken off.