If I understand you correctly there’s a conception problem. Nethserver can be the web host with all its features but can’t serve multiple clients like a service provider.
In other words: You may just buy a domain, set the nameserver record and host your domain with Nethserver but managing domains for the Nethserver users seems not easily possible to me.
yes basically nethserver has the potential to fork off into a webhosting provider platform like cpanel Plesk
It has the fundamentals backbone programs to do this already with what it already has built in
where you have one fork community based and the other business.
I know this would be a monumental task to achieve something like that im just thinking out aloud at the prospects of what I could use this platform for im just thinking of ideas and possibilities