It is multiple things based on a simple concept: no traffic should be discriminated based on source, destination or type. That means that netflix ones and zeros are treated the same as facebook, same as your web page filled with cat pics, same as torrents.
Can there be technical things why cerain services get lower level service?
I’ve read that ISP buys various links to to other networks at various prices.
So maybe something like: if facebookBar server is on pricier linkFoo and for that reason ISP buys cheaper version of linkFoo effectively downgrading facebookBar service (along with everything on linkFoo)?
If such scenario is realistic, maybe it could be due to valid financial stuff, not due to anticompetetive behaviour. (Just saying, some technically valid scenarios should be taken into account)
