This article outlines the motivations for the move:
https://learn.microsoft.com/en-us/dotnet/architecture/microservices/implement-resilient-applications/use-httpclientfactory-to-implement-resilient-http-requests
Unfortunately, this is only supported in .NET Core 2.1+, so to retain backwards compatability, this will need to be switched off of target framework, with legacy .NET Framework 4.x continuing to use the existing pattern.
This article outlines the motivations for the move:
https://learn.microsoft.com/en-us/dotnet/architecture/microservices/implement-resilient-applications/use-httpclientfactory-to-implement-resilient-http-requests
Unfortunately, this is only supported in .NET Core 2.1+, so to retain backwards compatability, this will need to be switched off of target framework, with legacy .NET Framework 4.x continuing to use the existing pattern.