Hi! I have tested vers=2.1 parameter on a current Buster installation and at least if the server is a Samba (samba as in Buster with a standard setup) the version of the protocol won't solve anything, the wget still breaks:
Saving to: 'STDOUT' - 16%[====> ] 1.01M --.-KB/s in 0.008s 2018-12-03 13:55:39 (124 MB/s) - Read error at byte 1056768/6538880 (Bad address). Retrying. The only working solution still is EnableSendFile On This was tested with: ii linux-image-4.18.0-2-amd64 4.18.10-2+b1 amd64 Linux 4.18 for 64-bit PCs ii samba 2:4.9.2+dfsg-2 amd64 SMB/CIFS file, print, and login server for Unix ii apache2 2.4.37-1 amd64 Apache HTTP Server Regards. -- Santiago García Mantiñán