Caching Google makes no sense beyond some static resources. Wikipedia can be made available off-line, just not by using a man-in-the-middle server. This may make sense for a school with limited connectivity to do.
> That’s great for modern browsers, but not everyone has the option to be modern. Sometimes they’re constrained by old operating systems to run older browsers, ones with no service-worker support: a lab full of Windows XP machines limited to IE8, for example.
You don't have the option to run legacy browsers and expect everything to work.
Just don't use a legacy proprietary OS if you want to go on-line with it. Either install a free (as in gratis, but libre makes sense too) operating system, pay for the windows upgrades, or scrap the computers.
Really? So you cannot make any sense of the idea of caching, say, news articles? Blog posts? Software documentation? StackOverflow Qs/As? The cached pages are 100% useless in your mind?
2. Blaming HTTPS is stupid. Intercepting http without the user knowing was a bad practice to begin with. Setting your own computer to use an HTTPS proxy sounds reasonable, though I understand it's quite a PITA. Having the user jump through difficult and scary messages could be a good feature IMO: "Setting up an https proxy can compromise your information such as bank account numbers, your passport information, your religious and political penchants, etc." As for technological solutions for one's home or organization: see Squid, which does provide examples [1].
[0] Wikipedia does care actually as it uses local cache a lot, and text-only articles such as https://en.wikipedia.org/wiki/Project_Xanadu used only 271 kB; https://en.wikipedia.org/wiki/United_States is around 5MB)
[1] https://wiki.squid-cache.org/ConfigExamples/Intercept/SslBum...
It baffles me that you assert this as an absolute truth. This is just your opinion, shaped by the environment you've lived in. It is perfectly possible that another person just as sane and knowledgeable as you would have different priorities than you do, especially when their experiences are different than yours.
A proxy and strict filtering of media files was essential when I ran a school's network using dual ISDN lines to connect to the Internet. Slightly analagous to the situation in OP except that it actually worked quite well.
