Is watching porn a dealbreaker?

My boyfriend who is 24 (I'm 29) watches porn. He says it's for "inspiration" and to "get ideas for us". But I know that porn isn't how real sex goes and it's very exaggerated and staged, unrealistic. Is it a red flag that he watches porn? Sometimes he'll turn on his phone to search something and be like, "Oh, don't mind all the porn. I'm getting inspiration for us." But then he just wants it the same way all the time, doggy style. (I'm not a fan, it feels a little degrading to me... am I just being a prude at this point?) I don't see any variety. Is this a "norm" in a relationship? How can I trust that he isn't looking at other women on Instagram or like OnlyFans or something? Should I tell him I'm uncomfortable with the concept of him watching porn?