I read that it was suspected to be damaged by a geomagnetic storm caused by the sun, not space junk:
Intelsat working to regain control of Galaxy 15 satellite - SpaceNews
But with the amount of space junk in low earth orbit now and the rate at which new stuff is put in orbit, it's only a matter of time until we get a chain reaction of collisions that becomes self sustaining and does massive damage. The movie "Gravity" comes to mind.....
The high earth orbit geostationary birds will be safe from space junk for a long time. Safe from the sun -- not so much!