There’s no way Bucky is resentful that Steve passed the shield to Sam. If anything, he’s fucking thrilled, because now he gets to work alongside another Captain America and laugh his ass off every time Sam makes a clumsy mistake.
Like I bet at some point Sam throws the shield and just completely forgets how math works, so when it hits the wall at one angle, it doesn’t come back to him.
Sam, taking the walk of shame to retrieve the shield: I fucking hate my life.
Bucky, wheezing and holding his phone: I got it on video and sent it to Steve.