That's actually typical pricing when there isn't a big event in town. The Driskill is sold out for many of the nights of SXSW and it's about $500/night when it does have availability.
Im used to seeing corporate rates at which all of them are well less than 250 for the three central city hyatts. Even on random weekends in march I see <240 prices for the Drisk.
Just chexked sxsw sxsw and most are elevated. Agreed.