My fuzzy impression is that vandalism tends, as is usual for such things, to be infrequent and unsystematic. So the larger and more persistent rest of the community can absorb the impact, and clean up after it.
Sounds a bit like Ted Nelson's notion of hypertext (pre web)! Also like the original web. Tim B-L's original Next-based browser had editing (thus POST). Mosaic was great for web popularity, but one wishes there had been a nice Xlib "text field" widget lying around, which NCSA could have been encouraged to include. Things quickly became broadcast only, and had to wait for forms to recover even a little. :( Imagine an alternate timeline where...
Theodor Holm Nelson, born 1937, obtained his BA in philosophy from Swarthmore College. In 1960, he was a masters student in sociology at Harvard. Shortly after enroling in a computer course for the humanities, he was struck by a vision of what could be. For his term project, he attempted to devise a text-handling system which would allow writers to revise, compare, and undo their work easily. Considering that he was writing in Assembler language on a mainframe, in the days before "word processing" had been invented, it was not surprising that his attempt fell short of completion. Five years later, he gave his first paper at the annual conference of the Association of Computing Machinery (ACM). It was around this time that he coined the term "hypertext."
"Never try to teach a pig to sing...it wastes your time and it annoys the pig."