Yes dispatchability is an issue with renewables. We need more transmission too. Both can be solved (and are being solved) with existing technology today, and both are improving all the time. It's both practical and economical today to build an off-grid house with PV and enough Li-Ion storage to bridge the nighttime gap and charge an EV.

With distributed electricity generation e.g. microgrids, the need for big, centralized storage decreases, as does the need for large-scale transmission.

By the time fusion generators exist in a practical form (at least 20 years from now), we won't need them.