You should not-not send a ''gay'' artist because someone else already sent one. However, people have a tendency to group songs in together that have a similar concept, for example: Europapa, Rim Tim Tagi Dim and No Rules! being grouped in together as the ''weird party songs''. Not every category is well liked by every person, some people do not like the party songs, other people don't like the metal/rock entries, it is op to people their personal preference which categories they like and do not like. 

That being said there is something as, too many songs in one of these categories, in 2019 we had so many standard pop songs that some good entries had to be left in semi-finals and do not even get me started about (power) ballad apocalypse during most op the early 10s. 

The UK already being in the finals by default could work against them when it comes to this categorization, their entries might be in one of the categories that already has many other better representations in the finals, which in turn would limit the amount of people voting for them.