Call of Duty: Ghosts (2013)\n\n A standalone entry with few connections to previous titles, Call of Duty Ghosts was developed by Infinity Ward in 2013.
In this instance at least, a truce has been called - not only is the bombastic shooter franchise going to be available on both Xbox and PlayStation consoles, a Verge report confirms that the deal is good for 10 years.
The proper answer is that your install size is bloated due to the game counting both the PS4 and PS5 versions. Since you bought either the Cross-Gen bundle or the Ultimate Edition, you get both versions, which can be played separately on your new gen console.