That's true. You must manually edit the up-to-6 config files to customize Homepage. It's not difficult, but it's not a GUI.
d.rymcg.tech is a docker-based self-hosting "platform", and it includes Homepage and a way to configure it using your own custom homepage-config repo, but that might be a bit much to take on if you just want Homepage or if thisnkind of thing is outside of your skillset.
Similar, at a company they asked the person cataloging the systems to write a yaml, then a dev wrote a script that converted it to html and then they asked a designer to slap some CSS on it. I don't think it took more than an hour of each person's time. Plus you can do each stage individually and improve it over time. For example later yet someone put the yaml in a git repo and threw together a simple deploy, someone made a script that pinged systems periodically etc.
I'm currently using Homarr but have used Fenrus and a few others and all work well you just need to find the one you like the best. The two I mentioned are simple to use and very customizable.