system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do modern graphing calculators have such a terrible resolution?
gpt
Some of the graphing calculator models have basically remained unchanged for decades. This has two benefits: 

1) it's all standardized so regardless of how old the calculator is, all the calculators of that model number will have the same features and functions and same sort of style/interface which makes it a lot easier to share calculators and teach groups of students how to use a graphing calculator.

2) Each calculator model is intentionally limited in its functionality. Even though the capability exists to make very powerful graphing calculators with amazing high-resolution 3D graphics and powerful mathematical functions without a significant increase in price, schools want students to be purposefully limited to certain functions found on specific calculator models. The primary reason for this is that it makes sure everyone is on the same page and that no student has an unfair advantage or the ability to use the calculator to 'cheat' and perform advanced functions/calculations that the school wants students to learn how to do manually.

Edit: by the way, there are other more advanced graphing calculators out there that have color displays and higher resolution displays, it's just that the most popular models (the ones that schools usually require students to use) contain only the basic functionality and low-resolution monochrome display that has been around for ages.