“It is what it is.”
The writers are NOT obligated to cater to your ship. They simply do what’s best best for the plot, characters and show as a whole. Expecting the finale to play out like the headcannon or fanfic of your dreams is not only completely unrealistic, its immature and self centered. There was never any queerbaiting in Sherlock, people simply saw what they wanted to see.
Why should the lack of what you wanted to see have the right to make the entire show awful? As an audience we were blessed with another spectactular season of Sherlock. If you wanted something different, go write the fanfic yourself, don’t expect Mark Gaitss and Steven Moffat to do it for you.