Whether waterlogged or not, fish of all kinds get stuck in glass panes, and seemingly the tops of blocks too. Even when not waterlogged, they don't suffocate however.
Smaller fish like tropicals and cods sink to the bottom, and salmon get stuck right in the wall. This potentially kills fish tanks people create.
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After checking further, part of the description of this issue seems to duplicate MC-144050, that being the water logged blocks.
In those cases it is an aquatic entity (in this case a fish) getting stuck on a water logged non-full block as what is described in MC-144050. In the cases where it is not water logged, this seem to be more an issue with the "follower" fish pushing their "school leader" into walls and mostly corners making them stuck. That causes all the fish to not roam freely anymore.
Updating the post to reflect this may be good.
Can confirm in 24w05a. I'm not sure if they actually literally get 'stuck' or if they just try to endlessly pathfind to areas outside of their aquarium
Can confirm for 20w11a, though it seems cod and salmon are affected too.