You need numbers.
How many gallons a day do you need?
How much sunshine can you expect? Duration and frequency? Maximum duration without sun?
How much pumped water storage is there, to hold over, between sunshine pumping events?
Without a battery, you need to pump and store all the water needed for that duration until next sun event.
I think it means a larger pump and more solar panels are required for short pumping durations. It also means that excess solar beyond what is required to fill the tank is discarded….unless pumped water is stored.
I think storing excess solar energy (either as “pumped water” or in a battery) and making a smaller pump flow for a longer time duration is more practical.
It’s like pulling a 5 ton trailer (1250 gallons) up a hill. You might need 400hp if you want to do it in 60 seconds, but a 1/2 hp motor will also do if you have all day.