Yes. All it takes to write good content is impeccable language skills, research abilities, and the ability to put your ideas into words. Extensive reading, and knowing what makes good content, can help non-native English speakers to improve their content writing skills.
Once they build a portfolio, the quality of work attracts clients and not the native language. Many non-native English speakers write better content than native speakers do. This is because their interest and attention to detail motivate them to improve with each piece they write.