Just get a DeeZee rubber bed mat. I had one in my F150 for 4 years, which had an unprotected bed otherwise. When I took it off after 4 years, the bed looked brand new!
Besides protection, big plus is that it prevents things from sliding around in the bed, looks great and doesn't scratch up delicate items that a spray-in liner's sand paper like surface would. They are also very heavy, won't flop around in the wind in a empty bed. That's why even though my new truck came with a spray-in liner, I still put in a bed mat. They make them for each brand and bed size, best $90 you can spend on your truck.
This is the one I bought, fits crewcab short bed models:
https://www.amazon.com/gp/product/B07MRKYQP5/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1