Do you find some mathematical activities useless?

[pier4r]

a good example of apparently not useful quest.

Plotting part of the solutions of 85 million cubic equations with integer coefficiens going from 200 to -200 (the equations were 25 billions, only 85 millions fell in range).
https://www.reddit.com/r/math/comments/8...lex_plane/

Now I wonder what they guy learned. because I am pretty sure one can get quite some patterns doing this.