PSD file format is big piece of sh*t and “specifications” provided by Adobe are a total shame.
Can’t tell if reverse engineering is complete or not, but…
I can understand the difficulties for someone coming from Photoshop to loose all files because not being able to reopen them properly on another software.
But on my side, even if I was paid for that, I won’t take a look inside this noodle box 
For what I already experiment, it was just like hell.
I personally prefer to see the 9 Krita’s full time developers working on improvement, bug fix, and maybe some new interesting functionalities than loosing their time to open a file for which specifications are modified on each software version.
Sure that in few years maybe Adobe will think about painters, but they might have an army of developers to improve their softwares.
And they probably already loose this place: Procreate is probably the next challenger for painting app…
Grum999