The only reason there was a competing evolutionary theory is because it was erroneously thought that birds have a clavicle and dinosaurs don't, so instead it was proposed that birds and dinosaurs have a common ancestor, and that dinosaurs lost the clavicle. Now that they have excavated many more bones paleontologists have since discovered therapod clavicles.
The scientific consensus today is that the evidence supports the idea that not all the dinosaurs died out when the Chicxulub comet struck 66 million years ago. The ones that could fly or quickly learn how to fly survived and even thrived, and their grandkids are in your back yard right now.
https://www.birdlife.org/news/2021/12/21/its-official-birds-...