I kinda liked how the old one, even though I guess it’s Lyra’s silhouette, was ambiguous enough that it could be a filly or foal, where the new random ones are definitely all* mares.
*Well, to be truthful, I can’t swear to have seen all possible combinations.
It’s worth noting too that this wasn’t exactly the original default either. It was initially a 125x125 PNG file. The SVG version was added about a year ago.