Having an additional stablecoin option for BTCB LP pairs would allow for more user agency, and open up more channels for funding liquidity into BTCB pools. BUSD is essentially a 'native' stablecoin for the Binance chain, and Tether (USDT) is the most popular stablecoin generally.
Creation of this pool would also increase global symmetry among the available options for primary tokens on PancakeSwap. Currently, both CAKE and BNB have BUSD and USDT pairs, but BTCB only has a BUSD pair. A BTCB-USDT LP pair would round things out nicely.