> Deciding whether something is netFramework 4.8 or .NET Core 5 or NET3000 or nEt5 or NET Common 2.0 is impossible.

It's gotten real simple in the last few years, and is basically the exact same flowchart as Node.JS:

    Do you need LTS support? --> Yes --> target the most recent even number (.NET 8.0 today)
      ^--> No --> target the most recent version (.NET 9.0 today)

Just like Node, versions cycle every six months (.NET 10, the next LTS, is in Preview [alpha/beta testing] today; the feature being discussed is a part of this preview) and LTS add an extra year and a half security support safety net to upgrade to the next LTS.

Everything else can be forgotten. It's no longer needed. It's no longer a thing. It's a dead version for people that need deep legacy support in dark brownfields and nothing more than that.