As expected. I once did a write up where I stated we haven't seen anyone over the age of 60 in their prime. Kaido (59) and Kizaru (58) are seemingly still in their prime and they are barely the right side of 60, the threshold were most seem to decline.
Garp, Tsuru, WB, Sengoku, Rayleigh, Neptune, Zeff, Don Chinjao, Lao G, Gan Fall, King Riku, Streussen - even Big Mom to be honest - have all been way past it.
And like I wrote in my previous post Kong (probably 5-10 years older than Garp and Sengoku which would put him around 83-88 years old) should be way past it as well. But I can very well imagine him having a technique similar to Lao G which allows him to fight as if he was in his prime for a limited amount of time.
Imu and Gorosei, who knows how they manage to stay relevant after all this time. Ope Ope?