I regularly have fresh fish, never freeze it. It is fine on the second day ie after say up to 32 hours, if on ice and then in gladwrap in the frig.
I agree that there should be no fish smell or it is not fresh.
The other point is that there is a major difference if it is killed instantly with an iki. Often my fishing
companion will miss the brain and the fish is still alive an hour or two later. You can tell the difference.
I also prefer to break a gill and let it bleed, which gives a whiter flesh.
it properly is quite difficult. You want to avoid overcooking but just have the final fraction cooked on the plate. (Tuna and other seared fish excepted.) Usually for a fillet this will be 45-60 sec per side, but this depends on heat and thickness. You can watch until the whitened part reaches the almost centre then turn. I prefer canola or olive oil
with a minimal hint of butter.
give much longer times which is wrong.
There is also a catch to grilling or barbecuing whole fish because the thickness varies. I prefer to leave the skin and scales on because it acts as a seal and then peels off in one piece.
I will never have fish in a restaurant because it is inevitably disappointing - usually not very fresh and overcooked. In fact at best it is likely to be some days old since the boats don't come in every night.
My sister was like the OP and didn't like fish until she had it really fresh and not overcooked.