I'll steal an argument Chas makes often, I think this was just having an investigation to hammer on. Whether it was valid or could have lead to anything was besides the point, it was all propaganda.
There aren't many signs for anyone in my neighborhood now but I'm in an opposite boat. I put Biden sign in my yard so my neighbors didn't think I was a shy Trumper (as if those exist).
my theory is that they're in a bubble of only people that love that kind of shit and don't realize they're fucked in the head.
side note: Susan Demas is one of my favorites on twitter. She's consistently terrific.