"unchecked" is the default in C#, and "checked" is opt-in, except for compile-time expressions (and System.Decimal, which always throws on overflow).
You can tell the compiler to use "checked" by default for a given project, but it's fairly rare to see that in practice.
I wish it was the other way around, but I guess they didn't consider the overhead of "checked" acceptable as a default back in 1999; and now it's a back-compat issue.
Because the change is on the Visual Studio templates to set the checkbox enabled by default, no need to change the language for something it already supports.
It was mentioned on one of the regular YouTube videos with the team, but I am failing to find it now.
You can tell the compiler to use "checked" by default for a given project, but it's fairly rare to see that in practice.
I wish it was the other way around, but I guess they didn't consider the overhead of "checked" acceptable as a default back in 1999; and now it's a back-compat issue.