Adding a minute or two to a new user, ONCE, is not a big deal to that user.
Most people click out of a website that doesn’t load within 3 seconds. This would absolutely stop a bunch of people from joining, and that includes good users.
You don’t need to prevent ALL interaction and viewing the site, the vast majority of people lurk, at least when they first look around. Requiring some cooldown, a few hours, or days, when someone makes an account is not a big deal as they would lurk anyway, and it would improve the site immensely. Send an email that they can now post when the cooldown is off, and it’s fine.
I could see something like this working, although it’s hard to overstate how quickly people will nope out of a site they’ve never used if the slightest hurdle appears. If someone lands here from reddit or Twitter, and sees something they want to comment on, they might make an account – but they could easily just move on and forget all about the place if the instant they make that account they get a “you can’t post for 24 hours” message. I don’t think an email would work at the end of that period, either, because I’m betting many users don’t attach an email to their account or don’t read emails from social media websites.
Maybe a “first 5 posts are free” approach would work? New users can create an account, create 5 posts/comments as fast as they want, but then the 24-hour cooldown period hits. Everyone but users who want to sign up and post a ton immediately would be largely unaffected, and that group of users would still get a sample before they’re directed to watch mode for a while.
