"The reason you see innocent tags like #gay being blocked on certain platforms is that they are still frequently returning adult content which our entire app was close to being banned for. The solution is more intelligent filtering which our team is working diligently on. We’ll get there soon. In the meantime, you can browse #lgbtq — which is moderated by our community editors — in all of Tumblr’s mobile apps. You can also see unfiltered search results on tumblr.com using your mobile web browser," said Tumblr.
Fortunately, these tags can still be searched on Tumblr website but it is revolting to know that the tags "gay", "lesbian" and "bisexual" are automatically regarded as pornographic particularly when the team of Tumblr spend hours to moderate tags as "lgbt" and also "rape" but does not hope to waste its time to moderate "gay", "lesbian" and "bisexual".