We’ve seen a couple of these while traveling down residential roads, but we never thought to question what they were. Thankfully, there are people out there whose curiosity knows no bounds, so they do all of the askings for us. That’s how we made it through high school.
Anyway, when the OP asked Reddit what this grid-like object was, Reddit responded that it was a grid reflector. Basically, these things reflect light from vehicle headlights to alert motorists of the presence of a pole, so, you know, they don’t crash into it. Lampposts could also help, but grid reflectors are a lot easier to make and install.