I think Barkleys problem was that he relied on that freak of nature WR too much and teams picked up on that. He has said as much a few times.
I think Stafford had the same problem with CJ this year.
Sometimes, it can be a curse to have a receiver that is that good.
"You’re out there playing against another man who is basically now trying to take your place and try and make your team lose a game and I’m not having that. I am going to do whatever it takes to protect my island and protect my team, first and foremost.” - Marcus Peters