Net metering changed when it become economically unsupportable as PV adoption scaled.
The same thing will happen with grid-connected residential solar + batteries. Rates will be changed to be based on capacity rather than consumption. There might, for example, be a charge based on your maximum usage during a period rather than total usage.
Yes, the formula for grid connectivity will need to change. In some places it already has.
Grid electricity incurs two basic costs. Generation and Distribution. Traditionally electricity was charged purely on consumption (ie Generation). This made sense when everyone bought all their electricity.
It makes less sense when I benefit from being connected all the time, but only actually purchase electricity when my batteries run flat.
It's like being able to make endless backups for free, but only paying to restore.
As with many other things I makes sense to align billing to cost to value. Thus the cost of "connectedness to the grid" needs to separate from the cost of "electricity consumed".
In my opinion electricity grid just like other infrastructure like road needs to be owned and maintained by government. 2-5 year contracts can be given out for maintenance and upgrades with performance and reliability targets to induce competition. Then connection to the grid charges can be charged to everyone according to the type of power connection and bandwidth they require. If this is not done as prices for solar and batteries keep dropping people will defect from the grid and the people left on the grid will need to pay more and more resulting more defections from the grid.
The same thing will happen with grid-connected residential solar + batteries. Rates will be changed to be based on capacity rather than consumption. There might, for example, be a charge based on your maximum usage during a period rather than total usage.