Turns out that after having a bad control arm bushing (which started the wacky tread wear) and going months without an alignment (which continued the wacky tread wear, not to mention the car vibration at 65 mph and up), caused the metal bits in the tire to start poking through.
But only in some places.
So, off I go to get an alignment (finally) and a rotation.
At this point,
I should have had these earlier. Even a Sunfire can handle the snow with four new tires. I look back on the wintery events that I’ve missed and curse my lack of car knowledge. Ah, well. Live and learn. In the end, I and my passengers are safer, and that’s good.