Mac's are competitively priced when you compare apples to apples (no pun intended). If you actually find a Windows machine that matches a specific Mac pound for pound, the Windows machine will almost always be at least as expensive, if not more.
Apple cannot go offering 7-10 year warranties on their machines. That is a terrible idea from a business perspective. It would essentially give their customers free reign to mistreat their machines because they know they would get it replaced anytime within the warranty.
We know what we are buying when we buy a machine. I could have picked a 4 or 5 hundred dollar Windows machine but I wanted a Mac. I knew that it is made with the same type of computer components as other machines and that those may fail over time. I knew that the warranty is 1 year and if I choose to extend that warranty, I can purchase Apple Care. Apple's warranty program and Apple Care option far outweighs anything the competition offers.
I have a mid to low end Mac in the scheme of their offerings(1,000 dollars). If I decide to add Apple Care I will have the machine covered for 3 full years from purchase date. Would I be pissed if something happens to where my computer becomes a paperweight right after my Apple Care warranty expires? Sure, but I also know it's a computer and that I cannot really expect a computer to last more than 3 maybe 4 years before problems start.
Had I had the funds and the need for a more powerful machine (let's say 2,500 dollars or so), my expectations for the life of the machine would not be higher than they currently are. I would simply expect that machine to perform at a higher level than the 1,000 dollar machine for same amount of time (3 maybe 4 years).
So yes it sucks that the OP's machine is useless after less than 4 years, but spending 1,000 or 4,000 on it wouldn't and shouldn't be any indicator of how long the machine lasts.