Is anyone keeping you from opening the bad instance in your browser? No.

If you want to go there, make an account there.

If every single person who walks on to that street gets instantly beaten, stabbed, or have pedophilia shoved in their face, I would absolutely want someone to stop me from walking down that part of the street.

There is a reason that 500-1000+ instances block these instances of their own accord, and it's because those instances don't provide any value whatsoever to any who decides to open it. It's dangerous to be connected with that kind of stuff at all, there is no neutral stance on this, because taking a neutral stance on allowing the bad actors is just enabling them, as well as opening instance owners and their users up to legal trouble.

There's a good reason most people have never heard of any instances on this list, and people who don't want any instances to be blocked would only realize how big of an issue this is the day that they do make an account on an instance that don't block them, and promptly have their all feed flooded with swastikas and lolicon.

If there's a street that says "walk down this street to get stabbed" I'd take a wild guess that that street should probably have a safeguard preventing people from walking down it, there has to be some level of moderation to keep things from falling into chaos.

Instances that do not defederate from these quickly become a Nazi bar. I chose my Lemmy instance specifically because of its stance on defederating from instances like these. I'd rather not have pedophilia, swastikas and hate on my all feed when I open Lemmy.

These are the top 50 blocked instances, with tons of instances blocking them, yet most lemmy instances aren't little 10 user instances, they has a full stream of content throughout the entire day. If this was an issue, it would've already happened on Mastodon which is much more popular and much more aggressive on average about defederating with instances, commonly having instances that have over 50-100+ instances blocked, yet are still connected with the vast majority of users.

Censorship is a perfectly valid moderation tool, and is the reason that any of these services are even usable at all in the first place. Without defederation, instance admins have to go through every single one of the tidal wave of reports that would inevitably come from these instances, and that would require a full-time team of a few dozen admins just to even begin to keep up with it, when most instances barely have a handful of admins at all, who are also likely juggling a career in addition to moderating their instance.

Edit: this ended up a bit of a rant, but I figure this thread was a good of a place as any for it. I have a lot of respect for all of the instance admins for voluntarily keeping the instances free from all of this stuff.