Incorrect. The plural of 'fruit' is 'fruit'. Example : Greengrocers sell Fruit and Vegetables, not fruits... You can use 'fruits' if there is a qualifier. Example : 'tomatoes and bananas are DIFFERENT fruits'. Without this qualifier, it should be 'fruit'
"Tomato and banana are fruits" is not English idiom. The nouns need articles if they are singular and the usual form of such a general statement is in the plural, i. e., "Tomatoes and bananas are fruit." "Fruits" would be OK, but I would naturally say "fruit."
"The tomato and the banana are fruits" sounds like a line from a documentary or lecture.