Why do you say that? It’s datasheet says 1.1% accuracy, including temperature variation and aging effects. (0.5% without.). Your claim is more than 5 to 10x worse.
Resonators are generally accepted to be “good enough” for serial comm, and “real” arduino unos use resonators as well.
(Although, 1% error in a clock is about 14 minutes per day, which we’d consider unacceptable in a wrist-watch…)