Not only Xiao S, but also many Taiwan Province artists and Minnan artists like to give thumbs up when taking photos. For details, please refer to the older generation of Taiwan Province artists, such as Chu Keliang and Wu Zongxian, who almost always give a thumbs-up when taking photos. As a native of Taiwan Province Province, the Xiao family also has the habit of giving thumbs up, so they only like giving thumbs up when taking pictures.
This kind of culture also exists in southern Fujian, for example. If you go to the rural areas of southern Fujian, if your grandparents see you and like you, they will give a thumbs up together to show their love and appreciation.
However, this action looks a bit funny, and people who don't understand it will find it strange.
Now in southern Fujian, only the older generation will continue to use this habit of giving thumbs up. Young people all know this habit, but they don't like giving thumbs up to express their love and praise. Therefore, in a few years, we may not see this custom of thumbs-up.
In addition to the small S family, many men also like to give thumbs up when taking pictures, especially some middle-aged men. You can refer to the heads of uncles in your circle of friends, suits and a thumb gesture representing success.
Probably a middle-aged man thinks this posture is very mature and will show that he is a successful person. There are also people in WeChat business, sales and other professions who also like to take photos and give thumbs up, because they are also a group of people who are very eager to succeed.
In short, the little S family took photos with their thumbs up because of local cultural habits, and some people took photos with their thumbs up to make themselves look like successful people.