"Four years later, the BBC would broadcast Star Trek for the first time. It's hard to see how Doctor Who could have survived against the colour, drama, and professionalism of American sci-fi."

https://shkspr.mobi/blog/2020/09/review-doctor-who-the-web-planet/
#DoctorWho 

 @2fd7551e Doctor Who has always been more science fantasy aimed at children. It wasn’t even trying to compete with Star Trek. If it had tried to it probably would have failed and faded into obscurity.