DAE Not understand this trend of cars setting one to two car lengths behind another car at a stoplight?

Like it says in the description does anybody else not understand this new trend of people setting multiple car lengths behind another car at a stoplight? It seems like very recently and frequently I encounter somebody sitting at a stoplight and then the person behind them is sitting like one and sometimes I see up to three car lengths behind the car that they're sitting behind. One-ish I can understand, for safety reasons. But the two or three length thing I don't get. I've been driving for a long time and occasionally see people do this but up until about a year ago this started becoming more of a regular thing. I feel like these same people are the one's that when on the interstate are riding on your bumper like 6 inches.