Earlier quoted context omitted.
You are ignoring battery life which is a useful consideration on laptops which appear to be the majority of pcs. 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.
I'm not ignoring them. I just didn't mention them in this comment. They fit in the same rubric. 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…
Isn't this backwards?