Why does `trims` default to false in writers?

[not-my-profile]

This was apparently changed in c4242f0/#64. Before trims defaulted to true and now it defaults to false.

This change broke trims in Inkstitch, see inkstitch/inkstitch#2813. For which I am about to submit a fix in Ink/Stitch by setting trims=True.

I'm still curious why it defaults to false.