Doubt is the commodity sold by the PR firms employed by the industry; & individuals within both DFO Stock Assistance & the ONPSF industry find it hard to admit they are part of a industry that has real-life impacts to wild salmon as most of those employees (with a few exceptions) are generally well-intended folks. Those well-intended folks usually suffer from cognitive dissonance and try to find a way to discount reality that conflicts with their beliefs; while the PR firms & the DFO comms branch get paid to lie. Money seems to overcome any doubts they have.
WRT that pic - seeing lice on a wild outmigrating smolt is not "extraordinary", but the sheer number of lice might be.
From what I can tell by looking at a 2D pic of a 3D container - it looks like a larger (~90+ mm) Chinook smolt to me that has turned his/her caudal fin up & to the left while swimming - it's doesn't look quite as "eroded" to me as it appears, but the bottom corner could be. The scales are missing off the top back end of the smolt - where most of the motile lice are eating the scales off the body of the smolt. The so-termed trailing "erosion" of said fins looks more like trailing mucus. Fish produce more quantities of mucus when they are stressed - and both capture & the motile lice are stressors.
I can easily identify ~40 motile pre-adult stages of lice on one side - and the earlier, darker lice are most probably Leps; while the later settled pinkish ones on the front are more likely Caligus. W/o magnification - it is difficult to spot the Chalmus & copepod stages - that are usually more numerous than the preadult stages because not all of them survive to the later stages of development.
So, yes this poor fish could have ~100 lice on each side or ~200 lice in total of all species & stages. One has to look at the developmental rate of the sea lice to infer when & possibly where these lice loadings happened.
It's a dead fish swimming as the numbers of (motile) lice per gram of fish that can cause mortality are in the range of 0.7 – 1.6 lice per gram of fish - dependent upon study, species & life history stage of the lice.