"If we do not change direction, we may end up where we are heading"
Fully realizing this has the potential to be derailed by our often lesser human polarizing tendencies, here some quick thoughts:
Our opinions and beliefs are likely to be biased towards our own individual experiences based on a relative short lifetime, we are prone to have issues with shifting baselines, so what was great for us may have been pretty bad for someone else a generation before, or even in our timeframe but in a different social/cultural/economic context. This affects not only our opinions and beliefs but also interpretation of actual data, if not put in the right context as mentioned by
@Stonedfish.
It is clear that salmon fishing (and other fishing, gathering, etc) was outstanding for pre-Columbian native Americans, just take as part of the evidence the amazing art they had time to produce instead of using that time for calories procurement. Those probably were the good old days for some.
When Captain Cook and other early Europeans visited the PNW, they had tales of walking on top of fish backs in estuaries, rivers, etc. Those probably were the good old days for some.
People that fished the area decades ago but in more contemporaneous times also have amazing to our ears stories of salmon fishing "back in the day", friends of mine sold their boats when fishing for king salmon became more curtailed in recent decades.
It is clear that we are in a downwards decline for salmonids in the PNW, depending on the species/stock/area we have some years that are outliers on both directions of better/worse than average, but that average is a long-term declining trend. In the future, 2023 might be sort of a banner year for me, at least in some areas/species I fish, but that would pale in comparison to older times. And then again, I am fishing mostly out of my boat, while in years prior it was beach + kayak or with friends with boats and earlier just from the beach, so it is hard to compare even my own experience over time.
I personally don't think there is a good answer to the OP question on "when were the good old days", just a long-term decline in stocks and fishing opportunities, where just in my short PNW salmonid fishing I have seen Steelhead gone (mostly), chinook becoming the "new steelhead", coho becoming the "new king salmon" (look at MA10 regulations in years past and in 2023), maybe pinks becoming "the new coho" and so on.
I try to have hope, but do worry about what may be left for our kids and future generations.
There is quite a bit of scientific literature on shifting baselines on natural systems and their relationship with humans, some specific to PNW salmon, see example below, which could be summarized by this sentence in the Abstract:
"Current salmon populations average 3% of 1950s–1960s abundances, which may have been 30% of precommercial fishery (1880s) populations.
Wild salmon and the shifting baseline syndrome: applicationof archival and contemporary redd counts to estimatehistorical Chinook salmon (Oncorhynchus tshawytscha) production potential in the central Idaho wilderness