For whatever reason, I can't find reliable information about this except for "Optimize connection buffer" turned on. I have 1/gbps Up/down the internet and it takes an hour to delete 50 small-sized directories. If I use Filezilla it's fine, any other file transfer program is fine. I love WinSCP but I cannot deal with this slow speed and can't figure out what is causing it! Even uploading an Mb file can take upwards of an hour. I've even done multiple sites and localhost, still the same issues!!
Haven't you enabled debug logging?
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