So a C# .net developer should know what?
Basic .net developer: (1 or more JS frameworks ex: Angular), HTML, JavaScript, CSS, C#, .net, LINQ, ORM(nHibernate), XML, SQL, T-SQL, …
Full stack: That plus, basic network administration (TCP-IP, BGP, routing tables?), basic windows administration (installation, security, back, scripts, deployment, troubleshooting), basic IIS administration (setup, matinee, troubleshooting), basic DB administration (deployment, troubleshooting, backups, clustering, profiling etc.), basic team foundation server administration, ...
Then to get an actual job you should know exactly the correct stack, including whatever wacky tools the team likes…
PS: And people wonder why they have trouble finding good developers.