This is more of a doctrine issue. Ukraine was given mountains of artillery by western nations, so naturally they were going to use it. But artillery has lower RoI than drones, drones are cheaper, more accurate, more versatile, and have longer range. It makes the most sense to heavily invest in the better technology drones, not artillery. If we look at what Ukraine spends its military budget on, >50% of its military spending goes towards drones. Only 15% is going towards artillery & ammunition.

We can also look at present wars to view where the trend is going. I'd estimate that during the latest conflict between Israel/Iran/US + gulf states, approximately zero artillery shells were fired*.

During a hypothetical US/China/Taiwan + Korean/Japan conflict, I'd expect this number to be similar.

*excluding rocket artillery such as HIMARS