Yeah, goalkeepers tend to have a longer career because they are not as physically active in the entire 90 minutes of every match. I'm still surprised to see many players like Cristiano Ronaldo and Messi still at almost their peak even though they are pretty old for football standards. I guess science and technology these days help to keep them active for longer.
Well.. that is surprising, because I always thought that the job of goalkeeper was a lot more demanding. It is very stressful and requires a lot of physical activity. And almost everytime, they are not given due credit. There have been some legendary goalkeepers in the past, such as Peter Schmeichel and Carlos Valderrama. But they are not given the same amount of respect, as given to forwards such as Diego Maradona and Zinedine Zidane. Anyway, this is just my personal opinion and others may not agree with me.