Raw means uncooked, not unripe. They taste sharper and have their skins on, and the seeds are with their gel and juice, between the firm fleshy parts. When tomatoes are cooked, often the first step is to drop them in boiling water for a minute, take them out, and slide the skins off. Because the skin gets tough when cooked. The other thing that happens in cooking is that the flesh softens and the seeds migrate so it’s all more or less the same texture. The flavor gets sweeter too.
Personally I like raw tomatoes and cooked equally, but they are different.