Watson does have a problem hanging on to the football. That will change though as he gains experience. If you watch, you'll see his hands aren't always in the right position to make the catches. That comes through coaching, and repetition. What he does do, and it's essential, is find ways to gain a step on defenders quite frequently, and that's something you either have, or don't have, based on speed, and ability to rotate your hips to change direction. When he solves the hands problem, he's going to be a load to contend with.
It's a lot like teaching a kid to play outfield in baseball. It's a matter of training yourself to have your hands and body properly positioned to make the catch. Judging trajectory is a key element, just like it is to a QB, when he throws the ball.
Until then, with the array of receiving talent we have on the roster, I'm not going to be too worried. I do think if it becomes a do or die situation for the team, Watson will more than likely make that catch, and if it's thrown to someone else, I hope it's Doubs, because he has the hands and body control to make it happen. He was injured on Sunday because he puts the catch first, and his body second. A lesser player would have protected himself, and forgotten about the importance of the catch, if possible.