PowerShell 7's Invoke-WebRequest is much slower than PowerShell 5.1's. In some cases four-to-five times slower, as outlined in this issue. But even measuring the most basic web requests between the two, PowerShell 7's is at least twice as slow. This is because it's based on System.Net.Http.HttpClient instead of System.Net.WebRequest.
What I'd like to know is if there is a PowerShell 7 function out there that supports all the same parameters, but calls the WebRequest .NET methods instead of HttpClient. That way, until this issue is properly addressed, I'm covered without having to change my scripts around, or at least not radically so.