No witness updates thier price feed every 3 seconds. We are talking about witnesses broadcasting "the current price of Hive is $0.427", not looking at actual trades (neither on internal market nor Binance).
Even if you could get new data every three seconds, you want the minimum value to be a reasonable value not a fluke fat finger trade. You want the price to stay below a certain point for a while (30+ mins under current implementation) to qualify as reasonable enough for usage.