For the right kind of storage, even high loss storage could be worth it, if it is long-duration storage.
The problem is economics with for-profit generation, not storage cost: If the cost of generation from PV was equitable, you would "store" your volts in the supply chain and withdraw from the bank over winter. Then the storage (at loss to transport) would be in Dams and other long duration spaces.
In most cases every residential system is getting payment rates at least that good.
The problem is that wH-for-wH doesn't take into account distribution costs, which is most of the residential cost of electricity, and that a wH at noon in July doesn't cost the same to generate as a wH at 2am in February.
For most jurisdictions you can look up the large industrial rates to find the wholesale energy rates. Residential solar is worth about half of that 'reliable' electricity rate.