If I look at some page and see some typo or something missing and I have immediate control to edit that section, then I might do it. Requiring to register myself beforehand and undergo the whole email confirmation shenanigans etc. makes it an effort which is too big to commit to in just that moment.
I understand you and feel the same. However if you register once, you can tell (your browser or in the wiki) to auto-login.
This may be a silly idea if you work from a public PC but it can make it more simple to just edit one paragraph.
There's been an update to Pangaea! Thanks. Someday someone will transfer the various guides to the wiki... as soon as I run out of things to do at work again, perhaps.