It really depends.
Assuming everything is in perfect working order, the laptop can potentially last a decade or more, exceeding it's service life.
But of course, individual components can and will fail. Hard drives can fail, batteries will wear out after a couple/few years, plastic can age and crack... but on the original core parts it'll last a while, best case.
But it also depends in the design and stuff. HP had the infamous Pavilion dv series laptops (late 2000's) that had bad thermal design which relegated many a laptop to an early scorching death.
However I have a Lenovo ThinkPad T400 and my friend has a Dell Latitude E-something (both are business class PC's and were direct competitors) that are similar in age and still tick. So if you're going for longevity over slimness etc. a business/professional grade laptop will be the ticket. Easier to source parts for too typically.
PC minimum requirements have also plateaued somewhat since the days of Vista so a computer will remain useful, for longer these days. (My dad has a laptop with Windows 2000 that still works perfectly fine, but its 96 MB of RAM and underpowered-back-then CPU means it won't be doing modern computing anytime ever.