Obsolete BinaryFormatter infrastructure

[kant2002]

Is your feature request related to a problem? Please describe

Given that https://docs.microsoft.com/en-us/dotnet/standard/serialization/binaryformatter-security-guide and overall plan to obsolete BinaryFormatter, is there time to do the same and mark constructors with (SerializationInfo info, StreamingContext context). Also all implementations for serialization can be put behind AppContext switch, so if somebody want risky behavior he should opt-in into it.

Example how it is handled with DataTable class https://docs.microsoft.com/en-us/dotnet/fundamentals/syslib-diagnostics/syslib0038

Describe the solution you'd like and alternatives you've considered

Other alternative is provide more blog posts, and guidance how to move out of this technology, and later on again obsolete it and eventually drop support 😄

Will this feature affect UI controls?

Potentially VS designer affected, maybe 3rd party-controls libraries.
They should be informed about change upfront, even if writing was on the wall for a long time.

[dreddy-work]

/cc: @JeremyKuhne / @merriemcgaw

[kant2002]

I think this is #1251 and #6267 , so my search foo was broken when I wrote this issue :(

[dreddy-work]

@kant2002 , We would be tracking this with epic #6267 and closing this as duplicate.