As a former sysadmin that once helped ride herd over around 1,000 servers, of which around 10% were Internet-facing, I've never been a fan of autoconfiguation when it comes to punching holes through the firewall. I've seen the tripwire logs, and it's sobering.
So enabling UPnP on my EdgeRouter-4 wasn't something I had on the roadmap, but when I ran into difficulty getting DLNA to work on the default VLAN, I thought it was worth looking into (never mind that, as I later learned, having UPnP turned on wasn't going make a bit of difference on my local network: another reason that mastering theory should always come before practice).