iPad Air 2020 scratches easily?

We are all other users here and, as such, cannot speculate as to why something might happen. We also do not know exactly what parts/mfr Apple uses - that would be proprietary information. Only Apple would know that. Something sharp must have come in contact with the screen.

Good luck!

Perhaps that you need to understand that there is a fine balancing act between scratch resistance - and drop survivability.

Glass optimised for scratch resistance is very brittle - and is likely to break if dropped, or subjected to impact. Glass that is formulated to offer good survivability characteristics are more prone to surface scratches.

Gorilla Glass is a trademark of Corning Glass. There are many types of glass that carry this trademark; of itself, the name does not infer specific resistance to surface scratches.

The environment contains dust - some of which is very hard and therefore highly abrasive. If an abrasive particle is dragged across a glass surface, damage to the surface will occur.

Use of a Screen Protector is a potentially contentious subject, but many users will use a good quality screen protector. The screen protector is a [relatively] cheap sacrificial layer - unlike the device screen which is the single most expensive component of your iPad. Contrary to popular myth, a good quality screen protector from a leading manufacturer (e.g., Zagg, Otterbox) will not negatively impact screen responsiveness or sensitivity.

In addition to the screen cover glass, your iPad screen has a both a “hard coat” (offering a degree of scratch protection) and further sacrificial oleophobic coating that is intended to repel oils and dust. Neither of these can provide total protection.

It only takes one unnoticed abrasive grit particle to cause irreparable damage to the cover glass. While it is a matter of personal choice, if only to offer piece of mind, I always recommend use of a good quality tempered glass screen protector. Good examples are not cheap - but are significantly cheaper than a screen replacement.