Yep, available to anyone. It's much more restrictive though. Basically you need a valid developer certificate to sign apps. You can use your own with a free developer account but you only get so many tokens per week and apps need to have their tokens refreshed weekly.

You can also use an enterprise developer certificate that lasts forever but if Apple revokes it then the app stops working until you get another working cert.

It does require you to turn on iOS developer settings by connecting to a Mac with Xcode installed to enable but then you can manage app installation and refreshing via an App Store like Alt Store. EU has different system where there is no limit on amount of sideloadable apps but the apps still need to be approved by Apple. Alt Store also have a EU specific App Store for that purpose.

I side loaded on iOS for a long time. Get Youtube++ for ad free and I forget the Reddit client I used that was side loaded as well. You can run the server on any PC or Mac that will handle side loaded apps and being on the same WiFi network allows the server to automatically refresh the installed apps. Only big downside is updates are not automatic or simple. To update an app you have to download the new app .ipa and then sign it like you were installing it fresh. Usually it picks up the existing configs and data though. So it's not a full app wipe.

The sideloaded subreddit is where I got into it through.