I'll give you that--sort of. While voting is relatively inelastic in both states, it's more so in GA. There's a higher floor to work with in GA, but the demographic trends are moving quicker in TX.
But yeah, if one moves GA to a purple state, kind of like VA was around 2004, the GOP is badly hurt having to defend another state.
That leads me to believe that the optimal strategy for Democrats would be to invest in Texas for expanding voting registration and infrastructure networks to establish long term potential growth while considering how to actually begin building a bench in Georgia for the more immediate future. Pulling off a win in GA this election cycle would motivate putting more resources into such an effort.