A screen protector, especially a thicker glass one, can fill in very fine scratches, making them much less visible while also preventing new ones.

Clean the phone screen thoroughly with a microfiber cloth and lens cleaner or alcohol wipe to remove all dust and oils.
Purchase a quality screen protector (tempered glass often works best for hiding scratches) designed for your specific phone model.
Carefully apply the screen protector according to its instructions, ensuring no dust gets trapped underneath and aligning it correctly.
Smooth out any air bubbles.
The adhesive fills the micro-scratches, refracting light differently and making them harder to see.

N/A - An effective, inexpensive way to cosmetically improve the appearance of minor scratches and protect against future damage.

Apply a Screen Protector to Hide Minor Scratches