I used to run a Windowed OS with real multitasking on a 33MHz 486 DX with 4MB of RAM! Sure, apps are a little more resource hungry these days, but there's nothing about multitasking or windowing that inherently requires tons of RAM. An iPad could for sure enable full multitasking without any problems. Apple has made millions of laptops that ran OS X perfectly fine with less than 6GB of RAM. It's just that iPad users aren't accustomed to having to manually manage which apps are open at any given time.
I have a 2019 Macbook Air with 8GB RAM and it runs OS X fine for dev work. RAM compression and fast SSD storage make a big difference. The newer Macbooks will have even faster SSDs.
I think the main reason Apple don't want to add lots of RAM to the base Macbook models is that it's the wrong compromise between battery life and performance for most users. They are probably betting on continuing gains in SSD performance obviating the need for additional RAM.
I have a 2019 Macbook Air with 8GB RAM and it runs OS X fine for dev work. RAM compression and fast SSD storage make a big difference. The newer Macbooks will have even faster SSDs.
I think the main reason Apple don't want to add lots of RAM to the base Macbook models is that it's the wrong compromise between battery life and performance for most users. They are probably betting on continuing gains in SSD performance obviating the need for additional RAM.