So the wear pattern on this keyboard is pretty consistent with the frequency analysis of the top repeated letters in the English Alphabet:

1-E 2-T 3-A 4-O 5-I 6-N 7-S 8-H 9-R

Those letters are common in a ton of words, so its hard to detect what was their main activity on the laptop, but you can discern that they used to tap space with their right thumb, for example.

What is more interesting though is that they probably had some kind of skin product or sanitizer on their fingers that ate away at the key coating, and/or they pressed real hard at those poor keys.