Why does tilapia and swai fish taste like catfish?
Swai and catfish are biologically related, but Tilapia is a Cyclid and as such quite far removed. I think the biological relation is not all that critical to their similar taste which you dislike though.

The taste of fish relies on a few factors such as:


Their living environment (Fresh, brackish, salt water)
The type of soil on the water bottom (silt, sand)
The diet of the species (other fish, water based plankton or bottom dwellers)


Catfish is a bottom feeding freshwater species and likely to have a relatively similar taste to other species that share their living environment and diet. As such I'm willing to bet you also don't like the taste of Carp very much.

Perhaps the solution lies in finding a fish that has a similar texture to Catfish but is a sea dwelling fish eater. That way you might get the appreciation from your eaters while being able to enjoy your own dishes more.