Its the 'plotting' that chews up SSDs.
Assuming you only had 512GB of RAM, you'd only be able to do 1 plot at a time (since you need 400GB per plot). Plotting to RAM would need to be 4x faster, but it isn't since you'll be CPU bound. So it would be both slower and more expensive.
Adding plots costs 100GB a time, so an 8GB drive can get you about 80. If you want to double that, you must buy another drive. Double it again, two, four, eight drives etc, and they're like $200 each.
The number of participating plots you are competing with though, is going up exponentially. That will double by itself in a couple of weeks.
So people in at the ground floor, who premined, will do great, the whale-sized farming operations with a significant fraction of the lottery tickets will do great, for everybody else every hour dilutes their chance of "winning" anything.
That's where the SSD problem comes from, during creation the 240GB is thrashed, it is reused for every plot made. So an 8TB storage for finished plots implies 80 finished 100GB plots, which implies 80 x 240GB of thrashing on the SSD to produce them.