Yes, myopic optimisation takes considerably more resources as components inherited from previous planning horizons are included.
We have rarely been able to solve networks requiring more than 300 GB RAM for non-hardware reasons.
For HPC systems, a CPU with high clock speeds and sufficient memory on one node (e.g., 512GB) would generally be suitable.
In the hydrogen network paper, we reduced the spatial resolution to 90 nodes for the sensitivity on temporal resolution, because it was impossible to solve hourly resolution with 181 regions.
The graphic shown there also shows that going down to 3h resolution does not cost much in accuracy.
You can also try the time segmentation clustering approach.