Why is USDT transfer fee so high?

I'm somewhat puzzled why the transfer fee for USDT is so high. Given its status as a stablecoin pegged to the US dollar, I assumed the transactions would be more cost-effective. Is it due to the complexity of the underlying blockchain technology? Or is it because of the high demand for USDT transactions that justifies the higher fees? I'm just trying to understand the economics behind this decision. Could you please elaborate on the reasons for the higher transfer fees?