He is wrong that it can't be fixed up well enough to bring heavy vehicles over I'm confident. Even losing whole span is not an insurmountable problem.
Of course it can be repaired, even if it would be destroyed completely it can be rebuild. The question is: how long will it take? Months? Years?
At this moment it is impossible to use the bridge for real military action. And Russia needs this bridge now. After the bombing of July 26 the damage has increased much, weakening the structure even more. Not only the holes are far bigger, there are also more holes and not only the top level is gone, even underlying levels are gone. You can see the water thru the holes.
And Ukraine will continue to bomb the bridge if Russia would try to repair it. The bridge is out for the rest of the war.