By "cultural changes" you mean energy shortages. Realistically, this would most likely result in leaders getting elected out of office and resuming the use of fossil fuels. Regular blackouts are immensely unpopular.

Cultural changes don't fix the duck curve. Around 4-7 PM is when virtually everyone is running their HVAC the most. This is also where you are starting to lose most of your solar generation capacity. There is a solid 4-5 hours of thermal momentum that needs to be compensated for before everyone hits set point temperatures and units cycle off on the hottest days.

Unless you are proposing that we do away with basic comfort in many regions, or spend hundreds of billions of dollars tearing down every structure and re-engineering them for passive comfort, I do not think there is much choice other than to bring in more peak generation capacity or employ currently-infeasible grid scale storage.