Never was any other way - the piscine equivalent to battery hens.
Unlike wild salmon who have ranged the oceans and fought every way to the estuary then, as they go off feeding, burning off every ounce of fat battling upstream, farmed salmon just sit in their cages get pumped full of antibiotics and other chemicals to battle sealice (as well as artificial colouring to get the meat pink) fed to them in their oily fishmeal pellets.
Salmon farming is extremely damaging to wild fish stocks as the 'cheap' food they are fed is produced by harvesting thousands of tons of 'off quota' fish such as sand eels (the staple diet of wild salmon and seatrout) thus causing a famine in the natural salmonid environment.
The massive concentration of sea louse spawn and adult lice deposited under the cages infest wild salmonid stocks compromising their health and breeding capabilities.
It also causes massive damage to the local eco system as the tons of toxic filth which is deposited under the farm cages is unbelievable,
IMHO everyone should boycott supermarket salmon.