IMO the main reason is high DPI screens. On macs it's essentially the default, and it'll probably become the default in the future for everything. Since bitmap fonts make much more sense with low pixel density I think it's not going to be a priority for any newly developed apps.
Bitmap fonts can be scaled by integer factors without losing any crispness, and most high-DPI displays in common use today would look just fine with a 2x or 3x font upscale.
Very disappointing. Not sure why people are trying to kill off bitmap support in everything these days. Will stick with foot.