I think the raw oils are not that bad (maybe in quantity it becomes an issue). Coconut oil I know is saturated fat, so that can be bad for your heart.
I think the bigger issue is how they are used in processed food. Just about every processed food has “partially hydrogenated soybean oil” or something like that, which is basically the worst possible thing for cholesterol.
It’s the same with how everyone started using Crisco because lard was thought to be unhealthy. It turns out heavily processed vegetable oils are worse.
Another solution then: automatically download/cache a user’s most frequently played tracks. I know downloading is a premium feature or whatever but they should consider it if it would save them money.