This curve has changed somewhat since this study in 2016. More efficient home insulation, remote working, and energy-efficient cooling systems have large impact in this pattern. But assuming you have a well-insulated home, setting your thermostat to maintain a consistent temperature throughout the day will shift this peak earlier and lower the peak load at sunset, when many people are returning home. More efficient heat pumps with variable pressure capabilities also helps this a lot, too.

Given just how many variables are involved, it's better to assume peak cooling load to be mid-day and work toward equalizing that curve, rather than reacting to transient patterns that are subject to changes in customer behavior. Solar installations are just one aspect of this mitigation strategy, along with energy storage, energy-efficient cooling systems, and more efficient insulation and solar heat gain mitigation strategies.

If we're discussing infrastructure improvements we might as well discuss home efficiency improvements as well.

I watch big state and national grid loads (for fun) and I see two distinct peaks: 7-8AM when everyone goes to work, and then around 5-7 PM when people commute home and heat up dinner.

Otherwise it's a linear diagonal curve coinciding with temperatures.

I personally try to keep my own energy usage a completely flat line so I can benefit from baseline load generator plants like nuclear (located not that far away).

For the same reason we want to subsidize solar production in residential construction even though it's more efficient and cost-productive to do it at-scale. Having energy production and storage at the point of use reduces strain on power infrastructure and helps alleviate the types of load surging ayyy is talking about.

It's not a replacement for modernizing our power grids, too - it simply helps to make them more resilient.