Depends on the nature of the friendship. If strong boundaries are in place, yes, friendships are fine. I have plenty of male friends, but I don't hang out alone with them or engage in long private conversations over the phone/text. I only interact with them in group environments, but I enjoy our chats and I would definitely call these men my friends. Also, I'm generally friends with the significant other/family of these men rather than just the man.
Ill also note note that my male friends are of all ages. Some are teen boys who are practically like little brothers to me, some are classmates who are my age, some are older men from church who I serve alongside in ministry, some are fathers of children I babysit, etc.
I wouldn't dare completely close myself off to friendships with my brothers in Christ, but I believe healthy, strong boundaries are necessary to maintain propriety.