I'm not active on Linkedin but you can see changes as they are made in the github repo I linked. Or you can subscribe on the ascii-collab site to see what people are drawing.
I posted it in a few discord servers and on reddit once so I think that's how the majority of people find it. I haven't made any attempt at SEO so I doubt many people find it on Google.
Hey, thanks for making yourworldoftext! Drawing an ascii town with friends on your site is what inspired me to make this.
In regards to dealing with spam, by far the most effective trick is to get very little traffic (how foolish of me to post my site here!)
The site also saves old changes even if they have been covered up so it's possible for me to remove vandalism and restore what was underneath.
Lastly I have a theory that people are more likely to spam if they see that there's lot of spam already and they are less likely if it looks like everything so far was written with intent. So I try to stay on top of removing spam as soon as it appears.
That could be a neat feature! It's already possible to get notified of changes via this link https://ascii-collab.app/notify-me but it's for all changes. Before posting to HN this site didn't get much traffic so this was enough but creating a notification area could be a good idea if a lot of people stick around.