On my iPhone the green bubbles are much more saturated and legible than in the posted article.
- Contrast of your iPhone: 2.21:1 (#35c759)
- Contrast that's "poor": 2.17:1 (#65c466)
- Contrast that's "good": 2.93:1 (#3bac3c)
- Contrast of the blue: 3.95:1 (#367bf5)
Based on this I would say that the Contrast of your green and the "gross" one from the article are actually pretty close, both being very far from the contrast that blue provides.
Not even the good green from the article does match the contrast of the blue. They are being lenient I'd say, not misleading.