Why are papaya and date palm plant said to be dioecious whereas cucarbita and coconut are said to be monoecious in-spite of all of them bearing uni sexual flowers?

Dioecious plants, like papaya and date palms, have separate male and female individuals, meaning that one plant produces only male flowers and another produces only female flowers. In contrast, monoecious plants, such as cucurbita (squash) and coconuts, bear both male and female flowers on the same individual plant. This allows monoecious plants to self-pollinate or cross-pollinate more easily, while dioecious plants rely on the presence of both sexes in proximity for reproduction.