I'm not horsing around; well I am but not about that!
I still get the dreaded 'Failed to Launch Server Application' error when I try to "edit bitmap" of any image over 50 MB. It's not for lack of RAM, I have 64GB installed. So that hasn't changed for me.
Photo-PAINT has the same 30,000 x 30,000 pixel limit as PS PSD file format, that may be it.