The Matrix and Vibe may no longer be made, but models are discontinued and plants closed all the time. Both GM and Toyota are still around to provide support for these cars. They share much of their platform with the ubiquitous Corolla, so many parts will be readily available and cheap. The other parts will be no scarcer than those of any other discontinued model.from the two biggest car makers on the planet. Anyhow, these are decent cars in a handy size, part wagon, part hatch, part crossover. The Kia Soul and Honda Element are two more boxy vehicles of similar size, as is the current Ford C-Max, only sold as a hybrid.
Other compact hatches I like are the Mazda3, Honda Fit (smaller), Hyundai Elantra GT and the older Elantra Touring small wagon, Kia Forthe hatch, VW Golf. I also like the Ford Focus and Chevy Sonic, bit both have had reliability issues. The Toyota Yaris is reliable, but not very nice, noisy and rough. The Nissan Versa is dismal, strictly bargain transport. For similar money I’d get either a Hyundai Accent, Kia Rio, or Mazda2.
Unfortunately it’s hard to make hard and fast used suggestions because cars get redesigned every few years. The current Yaris is maybe barely tolerable, but better than the one from a few years ago. A Ford Focus from a few years back is not so bad. It was simpler and more reliable than the current model, which is generally nicer.