Cat collars getting stuck can be a problem regardless of a bulky item being attached (though, it will probably be exacerbated by a tracker), so a breakaway/quick-release collar is a good idea in any case.
This is (unfortunately) very, very true. I don't have firsthand experience, thankfully, but 2x secondhand experience, and I cannot think about those two cases without getting tears in my eyes. It's not common, but uncommon things happen all the time in large populations.
