Yes, it is not uncommon for Chinese Indonesians to adopt native Indonesian surnames. In Indonesia, individuals are often identified by their family or surname. Historically, Chinese Indonesians faced discrimination and various challenges due to their ethnic background. To assimilate better into Indonesian society and to mitigate some of the discrimination, some Chinese Indonesians decided to adopt Indonesian names, including surnames.
The process of adopting Indonesian surnames began during the 20th century and gained momentum in the years following Indonesia's independence. The adoption of Indonesian names allowed Chinese Indonesians to integrate more seamlessly into the broader society and demonstrate their loyalty and commitment to Indonesia as a nation.
As a result, it is not uncommon to find Chinese Indonesians with surnames that are typical of the broader Indonesian population. Names like "Gunawan" are a good example of this. However, it's essential to remember that not all Chinese Indonesians have adopted Indonesian names, and some still maintain their traditional Chinese surnames. It depends on individual and family choices, as well as their interactions with the wider society.