[alkonaut]

In what way is the runtime not redistributable?

The old one “.NET Framework” is an OS component but has enough compat that you can always upgrade it.

The newer one (net5+) is typically fully bundled with each app so no sharing.

MSVC also went this way - you bundle them rather than take a dependency on a system wide runtime. These two (.NET and c++ runtimes) were basically the last shared libs on windows, and it’s now basically obsolete tech (.NET 4.X) or no-longer-recommended deployment method (Msvc).

[formerly_proven]

You are right, but there are still a lot of applications reliant on the "old ways".

[pjmlp]

Given that the new way for SxS was introduced in Windows XP, the old way is a long time ago.