Sometimes little thing jump out at you.
I was reading about the new fishing event to be released in 3.3.0 and it was mentioned that in 3.3.0 you never catch trash from fishing pools, regardless of skill. I don't know how I missed it the first time but I saw it there.
Because they are changing things related to fishing pools, watch those markets. I don't think this should create a large shift. Because it should be easier to catch fish in pools, expect more of those fish on the market.