Comment 12 for bug 1918141

For this I honestly see no risks of regressions for nfs-server.

Also, be aware that on systems using DHCP depending on network.target or network-online.target has the same effect simply due to the inherent ordering of DHCP packets not passing through until the interface is able to pass traffic.

When using static addressing it's essential that things that require networking to be able to handle traffic do depend on the correct thing, and that's network-online.target

Regarding the "my system hangs on boot" comment:

1) nfs-server is a server service, it's not something you run on a laptop or somesuch and expect things to work without networking.
2) Network startup has a timeout, so the system will boot eventually.

Do remember that one of the appealing things about Ubuntu/Debian is the main goal of services to "just work", and the most basic thing here must be to get at least the dependencies right for things to work in the common usecase for which the service is intended.

As a final note on nfs-server.service:

It currently does two things: Start the nfs-server and do exportfs. It's the latter that depends on network-online, so the startup could be split into two services with tailored dependencies.