That gap is between the right side timing chain and the upper guide, not the tensioner. The tensioner for that chain is at the lower left corner of the picture, and should apply enough pressure through the guide it is tensioning to keep the entire chain tight and up against both guides. I can't tell for sure, but it looks like the piston on that tensioner is broken. Compare your picture with the YouTube video timing chain tensioners at about 9:40 in the video. You see on your picture that square plate on the piston is right up against the metal boss on the tensioner. In the video, there is about a quarter inch or more of piston showing above that square plate.
But the answer to your question is that this IS a problem. Either the tensioner is bad, the chain is badly stretched, or a combination of both.
But the answer to your question is that this IS a problem. Either the tensioner is bad, the chain is badly stretched, or a combination of both.