Webdav copy is slow in SP 2013+ compared to SP2010

Hi,

First off, this is not an IE proxy setting I need to change - I've been there already

I have a problem with webdav performance. If I create eg. 20 txt files on my computer with a few words in each and copy those to a document library on SharePoint through explorer / webdav it is running 3-4 times as slow on SharePoint 2013 environment compared to an old SP2010 environement.

I have tried on both SharePoint 2013 and SharePoint 2016 environments running on servers running 2008R2, Server 2012 or Server 2016. All are slow.

On a SharePoint server running SP2016 that are slow, we have tried to create a seperate IIS website outside SP and enable webdav. Here it runs fast, so I assum this is something new in SP2013 and onwards? Can anyone confirm or is there some workaround I haven't noticed yet?

I guess we all should use onedrive and "sync" to sharepoint however some still prefer the old webdav method.

Hoping for some good inputs.

Thanks

Jan