Yes could be taken out by all that Chinese Missle test debris floating around by then.
So relax a little.
There is a rumour amongst Telesat that the 72.5 location is temporary to hold the license they have on that slot. Once Nimiq 5 is tested and activated, they will move it into position behind Nimiq 1 (or 2) I don't remember which, and they will shuffle the older satellite back to 72.5 for a specific future business application. This way they get to hold the 72.5 slot and will be upgrading one of the existing dbs satellites to more capacity in a few years and newer technology.
It is true that the new Nimiq 5 will have a more focused beam to reduce the spill over into the US.