It seemed crazy to me from day-1 they didn't have a "I want to always run my furnace fan" option since it is such a common requirement. And it seems to not exist to this date so when I want to turn my furnace off and circulate air I have to set the temperature to some goofy setting so the fan will run.

The last time I used the Google Home app I couldn't set my fan to continuous but the Nest app still allowed it. Seems wild to me that they don't have this basic stuff nailed down.