The problem (for me, anyway) isn't that git basically requires a command line to do anything - the problem is that git's command line syntax is exceptionally complex. I'm used to being able to do `man foo' and get a short listing of all possible orderings of parameters and arguments that a tool will accept. git's syntax is so powerful that it isn't possible to do this - a lot of the summaries in the manpages have the dreaded one-line `command [ARGS] ... [PARAMETERS] ...' that I tend to associate with a lot of the GNU tools.
Maybe if someone added an EBNF grammar to the documentation...
The point being that if 4chan users are (on the whole, anyway) too stupid to not spread JS viruses, asking them to not poll the servers so much is certainly a lost cause.
Getting the extension authors on board is probably the best option, because there's only a few of them, and they are not stupid. Stupid users don't have the skills to write broken extensions for themselves.
The only alternative would be (as others have said) to add auto-refresh JS to every page and thus bypass the need for extensions entirely. If the number of people who currently use these extensions is small enough, however, this could just as easily drive their traffic up because now every user on the site gets the same functionality without doing anything.
There's no accounting for an inconsiderate user base. This has always been a big problem for 4chan. I remember several instances where the site was effectively taken offline for days by a JavaScript virus embedded in PNG images that required the user to follow directions in the image in order to spread.
Maybe if someone added an EBNF grammar to the documentation...