I would never have imagined I couldn't add memory to an iMac. Yet that is the case.
If I run more than three programs, it freezes or crashes.
It takes forever to do ordinary chores, like do a Google search.
I use “Clean My Mac” software to keep it from being completely useless.
I will never buy another iMac. Apple is dead to me.
Here are the specs of my iMac:
iMac (Retina 4K, 21.5-inch, Late 2015
Processor 3.1 GHz Intel Core i5
Memory 8 GB 1867 MHz DDR3
Startup Disk: Macintosh HD
Graphics: Intel Iris Pro Graphics 6200 1536 MB
Won't run more than three programs without freezing or crashing? BS. I run up to 6-8 programs at one time (as I type this, I have 7 open) and don't have any problems at all.
Slow to do Google searches? Really? BS. Mine is lightening fast.
You probably bought the cheapest one you could find without any memory and it won't do what you want it to do. Always buy more memory than you need and make sure you can add to it if you want.
Everybody has their preferences when it comes to computers, smart phones, their cars, TVs, etc. But I've had Apple products since the mid-80's when they came out with the original Macintosh with a 5.25" floppy disk for a drive and have never experienced any of the problems that you complain about. Which tells me something else is amiss here.
You either got a lemon or you doth protest too much.