The lines you turned to sidewalks aren't sidewalks, they're address interpolations provided by StatCan (i.e., the government) osm.wiki/Addresses#Using_interpolation

Some of those roads do have sidewalks, but they're not the same as the address lines. In general, the sidewalks and address lines shouldn't match up (for one, sidewalks almost always have to intersect with streets, while addresses almost never will, but more generally they just aren't the same shape/location).

Also, some of the address lines you tagged as sidewalks don't have sidewalks on those roads. If you don't know whether a road has a sidewalk or not, it's best to leave it as is (or do a survey! :) ).

ugh did this just break another larger changeset? Feel free to undo this if it's easier, I can figure it out some other time.