Docker is only part of the puzzle. Even being proficient with Docker (and running services in a traditional way), there was always a big barrier to self-hosting for me in networking. If you lose all of your cloud-equivalent functionality once you leave your home network, it isn't a realistic alternative. I'm not a network whiz and the builtin VPN functionality of my NAS is sadly not up to par either.

In comes Tailscale[0], which made it dirt easy to self-host my stuff and have it available anywhere (given there is a Tailscale client for it which has been the case for all my devices). Since I started using it, I've completely migrated my contacts, calendar, zettelkasten (Trilium) to self-hosting and started some home automation projects. For someone who tried and was stuck at the networking part in the past, it truly is a game changer (and I'd like to think I'm not the only one that is held back by that).

[0] https://tailscale.com/