If you think about it though, would you rather them get together in the third one and then have a relationship that's rocky because of grindelwald, or, have them get together in the fifth one and the movie series ends with them being happy finally.
@Elizabeth Tawa yeahhhh, but already both Jacob and Queenie are ripped apart the second movie and Queenie and tina are too, which no doubt is going to rip a hole between them in their sisterly and romantic relationships- they could either go with the pair on opposite sides of a war fighting for the other even though that's not what they want, or they could get together the third movie and then have a rocky and awkward relationship for the last two movies until grindelwald is defeated