SftpClient: slow download

Hi! Thank you for this project, I appreciate your work.

I have a job in js that downloads some files over sftp every night using ssh2-sftp-client.
I decided to rewrite this job in C# using SSH.NET, but it turned out that the same files are now downloaded up to 15 times slower.
For example, a 25 MB file can be downloaded in 5 seconds using ssh2-sftp-client and in over a minute using SSH.NET.

I tested on ubuntu and arch linux in a simple .net 8 project. SSH.NET version - 2023.0.1.

using var sftpClient = new SftpClient(host, port, userName, password);
await using (var localFileStream = new FileStream("/someFile", FileMode.Create, FileAccess.Write))
{
    sftpClient.DownloadFile(file.FullName, localFileStream);
}

In case of reading from a stream it even slower:

await using var remoteStream = await sftpClient.OpenAsync("/someFile", FileMode.Open, FileAccess.Read, CancellationToken.None);
await remoteStream.CopyToAsync(localFileStream);

Do you have any ideas on what I should check or what settings I should play with?

Start with the SftpClient.DownloadFile and OpenAsync paths shown in the report, then reproduce the comparison in a simple .NET 8 project using the reported 25 MB file and environments. Compare the transfer behavior and relevant settings with ssh2-sftp-client; done means identifying and addressing the cause of the large download-speed difference.