https://www.aroged.com/2023/06/15/ssd-is-the-new-minimum-requirement-for-games-according-to-the-creators-of-starfield-and-cyberpunk-2077/
Of course. Storage space is cheaper on 7200rpm drives, and has, historically, for years. SSD is rapidly dropping in price, but it's not on the same level, yet. Western Digital Gold 4TB is $150 USD. Crucial MX500 4TB SSD is $200.
EDIT: SSD is also not available for large drives, 8-20TB.
6TB WD Black (7200RPM spinning rust) is ~$130 https://www.amazon.com/gp/product/B09NCMMSQX/ whereas a 4TB SSD is ~$150: https://www.amazon.com/Silicon-Power-Performance-Internal-SP004TBSS3A55S25/dp/B0BVLRFFWQ/
So you get slightly better bang for your buck with spinning rust but not much.
6TB drive really isn't a fair example, as hard drive sizes increase smaller drives aren't produced as much if at all. That has an effect of raising the price of the remaining small drives as your customer base becomes people who need that drive like if you have a drive go bad in a raid array and want a matching drive.
So while yes a 6TB 7200 RPM drive is $130, a 12TB 7200RPM drive is also $130.
https://www.amazon.com/Seagate-Exos-Internal-Drive-Enterprise/dp/B07YYKKJVZ/