C# verification that events GC when connected with static functions. This snippet proves that this is the case.

output.txt

----- BUILD EVENT CONNECTED -----

[HandleEventStatic] invoked with message Firing while we still have a reference

----- CHECK REFERENCE -----

[CheckReference] - ERROR: Object was not GCed
[HandleEventStatic] invoked with message Hello from check reference

----- FORCE GARBAGE COLLECTION -----

ObjectWithEvent deconstructor called

----- CHECK REFERENCE -----

[CheckReference] - SUCCESS: Object was GCed

StaticEventHandersDoNotPreventGC.cs

using System;

namespace TestEventBehaviorConsoleApp
{
    class MessageEventArgs : EventArgs
    {
        public string Message { get; set; }

        public MessageEventArgs(string message)
        {
            this.Message = message;
        }
    }

    class ObjectWithEvent
    {
        public event EventHandler<MessageEventArgs> Event;

        public void FireEvent(string message)
        {
            Event?.Invoke(this, new MessageEventArgs(message));
        }

        ~ObjectWithEvent()
        {
            Console.WriteLine("ObjectWithEvent deconstructor called");
        }
    }

    class Program
    {
        static WeakReference<ObjectWithEvent> BuildWeakReference()
        {
            ObjectWithEvent obj = new ObjectWithEvent();
            obj.Event += HandleEventStatic;

            WeakReference<ObjectWithEvent> reference = new WeakReference<ObjectWithEvent>(obj);
            obj.FireEvent("Firing while we still have a reference");

            return reference;
        }

        static void CheckReference(WeakReference<ObjectWithEvent> reference)
        {
            if (reference.TryGetTarget(out ObjectWithEvent outputEvent))
            {
                Console.WriteLine("[CheckReference] - ERROR: Object was not GCed");
                outputEvent.FireEvent("Hello from check reference"); // Use this incase the compiler is sane
            }
            else
            {
                Console.WriteLine("[CheckReference] - SUCCESS: Object was GCed");
            }
        }

        static void Main(string[] args)
        {
            Console.WriteLine("----- BUILD EVENT CONNECTED -----");
            Console.WriteLine();

            WeakReference<ObjectWithEvent> reference = BuildWeakReference();

            Console.WriteLine();
            Console.WriteLine("----- CHECK REFERENCE -----");
            Console.WriteLine();

            CheckReference(reference);

            Console.WriteLine();
            Console.WriteLine("----- FORCE GARBAGE COLLECTION -----");
            Console.WriteLine();

            // Force GC
            GC.Collect();
            GC.WaitForPendingFinalizers();

            Console.WriteLine();
            Console.WriteLine("----- CHECK REFERENCE -----");
            Console.WriteLine();

            CheckReference(reference);

            // Delay
            Console.ReadKey();
        }

        private static void HandleEventStatic(object sender, MessageEventArgs args)
        {
            Console.WriteLine($"[HandleEventStatic] invoked with message {args.Message}");
        }
    }
}