I would say it became much easier in recent years. docker-compose became defacto server "app install", any linux supports it. That includes GUI options like Truenas/Unraid and very nice admins like Dockge exist.

The company behind matrix is aiming at huge scale servers but if you care about unfederated private instances you will find there are few much simpler "one binary" projects that can even use file based sqlite/rocksdb. Hosting those couldn't be simpler. You actually don't even need docker just systemd service and switch binary when updating.

If you want a simple docker-compose for Matrix, you can always use https://github.com/element-hq/element-docker-demo.

The reason Element ships ESS Community as kubernetes helm charts is simply so that the officially supported distro is as close as possible to the thing we have to support for the big govtech customers, where docker compose simply isn't going to cut it. Perversely, that means that ESS Community is pretty bulletproof (even if the scaling stuff is missing), but comes at the expense of having to run k8s.