While the idea of a liquidity coin does exist, having to hold Bitcoin and somehow hold stablecoins doesn’t come together good. People tend to hold Bitcoin because of its volatility, the potential to increase over time and you making profit from it while, stablecoins just maintains its value. You don’t really need to hold stablecoins except you have that for an aim or need to use it in some active buys. Even then, you have the swap feature on exchangers and could always use that to do you bidding when the need arises.