Adding xml feed from another instance to a rss reader

Hey all, I have been adding community rss feeds by adding the community name + .xml to my feed reader. Works great for my home instance lemmy.ca but trying to add the .xml for a community I am subscribed to from another instance craps out with the login page requirement.

For example, adding https://lemmy.ca/c/lemmy411.xml works fine in the rss reader but adding https://lemmy.world/c/technology.xml does not work because I am not on lemmy.world.

Also https://lemmy.ca/c/technology.xml@lemmy.world fails with feed not found "Join Lemmy"

Any ideas? Maybe I am missing something obvious.