This is what I've witnessed in the recent past:
Don't worry, you'll be good for a long time Since 8GB is pretty much the desktop standard, and 4GB is (sadly) the laptop standard, and people very rarely get over the 16GB barrier, you should be fine with 8GB for a couple of years, and with 16GB, you'll have to worry about other components way before RAM becomes an issue. Software requirements are always held back by the specifications of systems currently for sale, and since we have a bunch of 4GB laptops, everything seems to be designed to run on these things. Even if 4GB goes off the scene during the next year, people won't instantly throw away or upgrade their laptops. It will take time until developers decide that they shouldn't worry about 4GB machines. And even then, 8GB will be that little thing holding them back so you'll be fine for some more time.
An application consuming 1GB of RAM on a 4GB machine is considered very unreasonable, even though it's normal to have 2GB eaten on a 16GB machine. So if software developers want their software to be used widely, they need to take that into account. Otherwise, these users with machines low on memory will start looking for alternatives.