Why is my network scanner so slow?

I scan all my incoming mail into Paperless-ngx. Nothing fancy, just regular letters and correspondence, duplex, 300 dpi, color. The volume isn&rsquo;t huge, but it annoyed me every single time: a duplex page took 45 seconds to go through the ADF of my Epson WorkForce Pro WF-C5890. That&rsquo;s a long time to stare at a scanner for a single sheet of paper, and it was bugging me enough to actually…