I rather doubt there are any statistics on the very small population of gay celibates in general, let alone the surely miniscule subset of gay celibates who adopt.
Besides, I do have an example in mind: William Alexander Percy, who adopted his nephew (later novelist) Walker Percy and his two brothers, after the separate apparent suicides of the boys’ father and mother.
“Uncle Will” evidently did a wonderful job raising the Percy boys. He did not expose them in the slightest degree to his sexual disorder, which actually came to attention only with the posthumous discovery of some of his poetry, as I understand it.
“Uncle Will” was celibate and lived his life in an honorable manner. His nephew, Walker, respected him deeply and expressed his appreciation of him in his memoirs.
“Lanterns on the Levee: Memoirs of a Planter’s Son” is his autobiography.
Read this story and then spend sometime googling. Most gays are adopting children to use them as sex toys.