My bet is Blender will become more standard in the next 10 years. It’s becoming big in gaming (I’ve heard)
They also break the API accidentally frequently. My favourite is that they have accidentally inverted the direction of rotation of the rotation operator 4 times since 2.8 and randomly removed one of the modes that the UV Smart project operator worked in.
The documentation is also lacking for the API and none existent for the main code base.
Despite this Blender is amazing but I do wish they were more professional. From a developer point of view the two things that would make life vastly better is if they
a) hired a technical writer to produce decent docs
b) stopped breaking the API every 5 minutes and when they did documented it properly (and in advance)
So, not such a bad decision. Building with MSVC used to be a bad decision, less so now.
Having to have divergent code paths per version is hell.
Blender has a Python API. Which is arguably one of the easiest languages to keep a stable API in, since you're not dealing with an ABI.
Yet that breaks regularly.
I'm okay if I had to recompile for every version of maya I support. I just don't want to have to have to maintain tons of ifdefs per version
Blender is indeed great but Maya is still extremely popular and many professionals happen to prefer Maya for one reason or another. I don't often see that fine grained of a discussion of media tools here.