Human power use has remained pretty constant in the past 60 years, at least if you just count the west. It was exponentially growing before then, which is why people had so crazy ideas about the future since they were used to exponential power growth and assume that would just continue.
So point is that no power grid hasn't grown as demand increased, rather we tempered demand to match that the grid didn't grow. You even see it today with power shut downs etc rather than increasing grids.
Even if our demand increased in terms of output, we curbed the demand in terms of input by increasing efficiency. My whole house's lighting requires less power when compared to two rooms' lighting power requirement 20 years ago.
That happened since we couldn't make more power so only way left was to increase efficiency.
Power used to be like how we see compute today, exponentially increasing so everyone wasted with it since you soon had more than enough. But once that stopped power efficiency suddenly became very important.
So point is that no power grid hasn't grown as demand increased, rather we tempered demand to match that the grid didn't grow. You even see it today with power shut downs etc rather than increasing grids.