How did many older men who had seen the first temple react when the new foundation was laid?

Answer: They wept loudly

Older priests, Levites and family heads who had seen the first temple wept loudly, while many others shouted for joy.

“But many of the older priests, Levites, and family heads who had seen the first temple wept loudly when they saw the foundation of this temple. Still, many others shouted joyfully.”— Ezra 3:12 (BSB)