I wish there was an easy way to correct typos online for the sake of the next person. I understand that this would open the door wide for abuse, but I can dream, right?
But the drawbacks might unfortunately make it not worth the effort indeed (people can get easily offended, the extension could have privacy issues, could be abused, etc).
Years ago I had developed a small module so people could submit fixes to my website. It's not up anymore.
In the end, many people don't care that much too.