While it is certainly possible for a 3D printer to produce a good quality TT (table tennis) ball in the future, it's worth noting that the current manufacturing process for high-quality TT balls involves a combination of high-tech machinery and skilled labor.
TT balls have very specific requirements in terms of size, weight, bounce, and spin, and they must meet strict quality standards in order to be used in official competitions. Producing such high-quality balls requires a significant investment in specialized machinery and skilled labor, which is likely why there are relatively few factories that are able to produce 3* quality balls.
It's possible that the cost of producing high-quality TT balls is a factor in why they are relatively expensive, but it's also worth noting that there is likely a limited market for such balls. Table tennis is a popular sport, but it's not as widely played as other sports such as soccer or basketball, which means that the demand for high-quality TT balls may be more limited.
That being said, as technology continues to advance and 3D printing becomes more sophisticated, As you can read
this information that it's possible that 3D printers could play a role in the production of high-quality TT balls in the future. However, it's likely that there will still be a need for skilled labor and specialized machinery to ensure that the balls meet the strict quality standards required for official competition.