Recent updates to BIOS or drivers on Windows 10 Home with Dell XPS 15 9500 are causing constant or intermittent fan operation.  Ambient temperature is 67 deg, no applications running, no third party AV or other high-CPU draining applications in memory. This is an ultra-vanilla installation with all the junk software uninstalled.  In fact, Task Manager is basically idle.

Fan is constantly spinning at a relatively low speed (compared to when you're gaming).  But there is no reason any active cooling should be needed.  Laptop is on battery at 80%, with Battery Saver enabled, and has less than 4 hours remaining which is unusual.  When I first got this in July 2020, I could get 10 hours.

Laptop has plenty of free ventilation and the bottom, back and sides are not blocked.  Screen brightness is at 50%.

It wasn't always like this.  Dell, what did you do?