Lower end 4TB SSDs were around $130 a while back (summer or fall of last year). I bought an 8TB hard drive for about $100 around that time since I just wanted archival storage. Since then, prices for both SSDs and HDDs have gone up. Still, I think for most people 4TB should be more than enough and I have a feeling that prices could’ve gone even lower back then but they want to keep prices high and they also want to keep segmentation between HDDs and SSDs instead of erasing most of the market for HDDs.