As a participant in commemorative events over the decades, Yao witnessed the profound impact of grassroots exchanges.

"The value of people-to-people exchanges lies in fostering friendship among ordinary people, which in turn opposes war and pressures governments to move with the tide," Yao said.

He also noted that China sent more than 600 coaches to over 100 countries to promote the sport and friendship worldwide.

Xu Yinsheng, the honorary life chairman of the ITTF, said time had aged the witnesses, but the friendship endured. Despite the current international climate, Xu firmly believes that grassroots friendships should remain unaffected by political differences.

"Regardless of any disputes between the Chinese and US governments, grassroots activities must continue to uphold and pass on this friendship," Xu said.

This year's Shanghai events featured table tennis and flag football matches, plus tech innovations, including humanoid robots and smart table tennis serving robots.

Xu said that while communication was once limited to in-person meetings, phone calls and text messages, young people today connect in new and more effective ways.

"Technology will introduce exciting new elements to table tennis, and future modes of exchange will be far more diverse than before," he said.

The delegation will also visit the ITTF Museum, Yuyuan Garden and the Shanghai Kunqu Opera Troupe, retracing the 1971 journey.

"We are all ping-pong diplomats," said Hoarfrost. "Sports, culture, music and education exchanges all promote understanding between people."

Li Junfeng contributed to this story.