Asynchronous TCP network server with a packet system

So I’m writing a game emulator and would like some advice after finishing the networking. It is designed to accept multiple connections, and process messages from all of them.

Here is just a brief introduction to the packets and how they are structured. [lengthOfString:short][stringEncodedInUtf8:Byte[]]

Let’s start with the NetworkHandler – this class is responsible for accepting new connections and storing them in the collection.

public class NetworkHandler : IDisposable
{
    private readonly TcpListener _listener;
    private readonly IList<NetworkClient> _clients;
    private readonly ClientPacketHandler _packetHandler;

    public NetworkHandler(TcpListener listener, IList<NetworkClient> clients, ClientPacketHandler packetHandler)
    {
        _listener = listener;
        _clients = clients;
        _packetHandler = packetHandler;
    }

    public void StartListener()
    {
        _listener.Start();
    }

    public async Task ListenAsync()
    {
        while (true)
        {
            var tcpClient = await _listener.AcceptTcpClientAsync();
            var networkClient = new NetworkClient(tcpClient, _packetHandler);

            _clients.Add(networkClient);

            networkClient.StartReceiving();
        }
    }

    public void Dispose()
    {
        foreach (var client in _clients)
        {
            client.Dispose();
        }

        _listener.Stop();
    }
}

Then we have the NetworkClient, I made this so NetworkHandler could stay small and to follow SRP – This class handles incoming data from the individual connection (client).

public class NetworkClient

{

    private readonly TcpClient _tcpClient;

    private readonly NetworkStream _networkStream;

    private readonly ClientPacketHandler _packetHandler;

    public NetworkClient(TcpClient tcpClient, ClientPacketHandler packetHandler)

    {

        _tcpClient = tcpClient;

        _networkStream = tcpClient.GetStream();

        _packetHandler = packetHandler;

    }
    public void StartReceiving()

    {

        Task.Run(ProcessDataAsync);

    }
    private async Task ProcessDataAsync()

    {

        while (true)

        {

            using var br = new BinaryReader(new MemoryStream(await GetBinaryDataAsync()));

            var messageLength = BinaryPrimitives.ReadInt32BigEndian(br.ReadBytes(4));

            var packetData = br.ReadBytes(messageLength);
            using var br2 = new BinaryReader(new MemoryStream(packetData));

            var packetId = BinaryPrimitives.ReadInt16BigEndian(br2.ReadBytes(2));
            if (packetId == 26979)

            {

                await WriteToStreamAsync(Encoding.Default.GetBytes("<?xml version="1.0""?>
Solution
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