Believing that either the Reddit exodus was negligible to that community, or that it was entirely decimated and left to Lenny are both inaccurate opinions. There was a very tangible effect on the selfhosted subreddit specifically when many left for Lemmy, and now both communities both feel like two halves of the same whole. Enough people moved over to lemmy that I truly don’t feel the need to open reddit hardly ever, but I do from time to time. I think lemmy also has a benefit that other fediverse sites like Mastodon don’t, in that Lemmy is not quite as allergic to the concept of discoverability, and the fact that Lemmy is inherently based around communities means that you don’t have to do the Mastodon thing where you spend the first month having to go out and follow a ton of individuals. You can just follow a couple communities and the content flows in.
Unfortunately not as self hosting is really just an amalgamation of a number of different technologies, concepts, groups of best practices, and there are nine and a half viable ways to do any given thing you’ll want to do. For my day job I manage several public systems that serve millions of requests a day and even I can’t really give you a “One definitive way of doing things”, but I have my preferences.
I think if you wanted a rough plan of what would be the most valuable things to learn in which order it would be
Docker, especially persisting your storage and also how its network works. Use containerized services only on your local network at first to get a feel for things, and give yourself the ability to screw things ip without putting yourself in any danger.
VPNs and how they work. You can start with a direct stupid simple VPN like WireGuard, or Tailscale if you want a mesh-VPN. This will allow you to reach your services remotely without having to worry too much about security and the micromanagement that can sometimes come with it.
Reverse proxies for things you’d like to expose to the public. At this point you want to learn as well about things like server hardening, have a system in place to automate software updates etc. there’s a common misconception that using a reverse proxy is innately much safer than port forwarding directly to your services. It can help by obscuring your home IP, and if you pair it with a WAF of some kind that’ll help you with much of the chaff attacks that get tossed your way, but at the end of the day in both cases you’re exposing the web services on your local network to the internet at large, so you have to understand the risk and reward of doing this.