Why has the 463-generation Merc G-class been surviving for almost 25 years?

Examples:
Most recent Ford Super Duty F-series - 16 years, since it's based on the 1997-'03 F-150
K-body Toyotas/Lexus = 14 years
But the most recent G-class is 25 years old almost!Why has the 463-generation Merc G-class been surviving for almost 25 years - 1

Militarys over seas buy them like the Hummmer 1 in the USA

"Most recent Ford Super Duty F-series - 16 years, since it's based on the 1997-'03 F-150 "

Nope. The current Super Duty only goes back to 2011. Furthermore the Super Duty was not based on the F-150.

"K-body Toyotas/Lexus = 14 years "

Not sure what you mean by K-Body, but the Land Cruiser/LX's current generation only dates back to 2007

"But the most recent G-class is 25 years old almost!"

Again, that's not the case. The G-Wagen saw updates in 1997,2005, 2006,2007.2008, and 2012.

G-Class is almost hitting it's 40th birthday actually lmao. I own one, the car is bulletproof tank that armies and other services use it. There's no reason to change the cars looks plus fans of the G-Class will lose their minds over it if they do lmao. My 2002 G-Class looks like a 2009 G550 because I changed the Grille and tail lights

Hi the G wagon is a utility vehicle designed to last for military purposes. How ever some toyota land cruisers have been found to last as long. Hence why it now cost around 80k pounds.