This is a little unusual. Most games never explicitly say you need an SSD or a HDD - but Starfield does! This likely isn’t a hard limit, as recommendations are often just that, but I cannot help but wonder what would happen if the game is run on an HDD?
Here’s me who has been playing games on SSD for the past 8 years. Just wait until they start requiring M.2 with specific read/write speeds. :)