I’ve chased a misfire on my 4 cylinder. Turned out to be a teeny weenie crack in the insulator. I didn’t notice it until after I changed the plug. Only after changing the plug and the misfire was gone I closely inspected the plug to find a very small crack.
How many miles on this truck? Spark plugs have a replacement schedule and that will be in your owners manual. It Takes he interval will range from 30k to 120k depending on the type of plug used, the plug in the picture looks like a single platinum tipped plug that usually get changed every 60k miles.
If those are the original plugs and you are close to or have gone over the recommended replacement interval, then all the plugs should be replaced regardless of how they look.
Edit: I looked it up, your replacement schedule for the spark plugs is 105k miles. It’s in a separate maintenance booklet that came with the truck.