It absolutely indeed makes no sense to buy 1 (one) 64-bit adm processor and expect it to withstand 5 years of upcoming techonolgy.
Then again , it makes no sense to assume any pc you buy now is going to work on technology invented in 2009.
Upgrading only makes sense if your requirements have also upgraded. If you still run games that will flawlessly run on a 486 machine , don't upgrade. ever.