Get-Member doesn't consistently show members that are explicit interface implementations as such

Prerequisites

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Steps to reproduce

Get-Member -InputObject (1, 2) Add, Count

• The .Add() method is properly reported as a member of the explicit implementation of the IList interface - see https://docs.microsoft.com/en-us/dotnet/api/system.array.system-collections-ilist-add

• By contrast, the .Count property is not reported as a member of the explicit implementation of the ICollection interface - see https://docs.microsoft.com/en-US/dotnet/api/system.array.system-collections-icollection-count#system-array-system-collections-icollection-count

Expected behavior

TypeName: System.Object[]

Name  MemberType Definition
----  ---------- ----------
Add   Method     int IList.Add(System.Object value)
Count Property   int ICollection.Count {get;}

Actual behavior

TypeName: System.Object[]

Name  MemberType Definition
----  ---------- ----------
Add   Method     int IList.Add(System.Object value)
Count Property   int Count {get;}

Error details

No response

Environment data

PowerShell Core 7.3.0-preview.5

Visuals

No response

Run the provided Get-Member reproduction on PowerShell 7.3.0-preview.5 or a current build, then trace the Get-Member implementation and its member-reflection handling. Done means explicit interface members such as ICollection.Count are displayed consistently with IList.Add, matching the expected output.