You are also ignoring the notion that a user may want to run a variety of apps, and not want to close or have any of the lot swapped out and pretending the hit on performance, resources, and battery life isn't cumulative.
A user can run a few things even on the low-end netbook. Tabs are cheap. And if they hit the limits of their machine, they can either pay in a reasonable number of user-minutes to actively manage resources or a modest number labor-hours to get something beefier.
I personally would like to see things better optimized. After all, I started programming on a computer with 4K of RAM. But I recognize that there is very little economic incentive to do so.
Isn't this backwards?
Try doing the math here. How much cheaper would a netbook get if every single developer coordinated to reduce RAM and CPU usage? $5? Maybe $10? Looking at market prices, old RAM and CPUs are cheap. They consume basically the same physical resources as new RAM and CPUs, so price competition for not-the-best hardware is fierce.
Now ask those people if they'd pay $5 or $10 more for assorted new software features. Any features they can think of. And keep in mind that in that price range, people are paying $10 more to pick the color of their computer.
So sure, it offends me a little, because I like optimizing the things I pay attention to, like RAM usage. But if instead I optimize for the sorts of the things users care about, especially as reflected by what they'll actually pay for it becomes pretty clear: users don't care about the things I do.
So then the moral question becomes for me: who am I to impose my aesthetic choices on the people I'm trying to serve?
This is especially true as people are promoting everyone moving to a platform that is substantially worse.
How about getting more performance and battery life out of the same machine which effects more than netbook users.
You may have noticed that we are in the technology industry. That means the final measure of our work is economic. The final judges of our work are our customers.
If you believe that X is better in our industry, you must be able to demonstrate that betterness in terms of user economics, in terms of user experience. You haven't yet, and you seem unwilling to even grapple with my argument in those terms. Are you planning on trying?
I wouldn't mind a true low-power laptop which only needed a charge twice a month.
What you propose is interesting though none the less. What is the most battery life that can reasonably be packed into a device that is modest but still useful.
Sure, and Office in the 90s didn't feel any faster than the word processing I was doing on an Apple II+ in middle school. This is because the people buying (and building) software care about other things than processor efficiency. If it's generally fast enough for their normal use, they won't switch to a competitor.
The notion of "wasteful" here is in terms of something like RAM usage or processor instructions. But the correct measure is user time, including the number of user hours of labor needed to buy the device. The original Apple II cost 564 hours of minimum wage labor, and you were up over 1000 hours if you wanted a floppy drive and a decent amount of RAM. Today, a low-end netbook costs 28 hours of minimum wage labor.
Suppose you managed to put on that netbook something with the efficiency of Apple Writer or Office 4.0. Would anything be better? No, because the spare cycles and RAM would go unused. They would be just as wasted. No significant number of user hours would be saved. Or, alternatively, the in-theory cheaper computer they could buy would save them very few working hours.
As long as the user experience is as good, then the hardware notion of "wasteful" is a theoretical, aesthetic value, not a practical one.