I agree with Riiiiik, but it goes deeper than that.
A commentator is useful to identify players and let you know what's happening in the areas of the pitch not covered by the camera following the ball.
For years now they've been far too ready with their opinions, which nobody needs, and perhaps worse every one of them is always searching for the bon mot. They must have pages of ad libs ready so they can shoehorn those in.
Although he intended it for cricket, they should all be forced to learn Richie Benaud's rules of commentary until they can recite them.
As for the ex-pro match summarisers sitting alongside them... that's something else I hope Jimmy Hill had to answer for when he went to meet his maker.