This is a salad with a slab of grilled tuna on top. The flavor was way off. Also, I can't imagine making tuna salad with fresh tuna. So, even with fresh tuna easily available, and even with the culinary current that all things must be fresh weighing down upon us, we must conclude that canned tuna has a place on the table. But now that we know all about fresh tuna, some aspects of canned tuna suddenly seem mysterious.
Most tuna is cooked inside the can.
To get the same effect with fresh tuna, you'd put it in a pan of lightly boiling, well-salted vegetable stock for something like 40 minutes. What you'd get would, when cool, taste a lot like canned tuna. The best quality canned tuna is solid-pack. This means that the entire contents consist of one continuous piece of fish. That's what you want for the likes of tuna nicoise.