You are spot on. They are in it for the money.
HOWEVER...
I came back to FSX/P3D 3 years ago after 10+ yrs. Whe I left I was on FSX: SE. When I came back it was looking exactly the same as when I left flughtsimming. Same goes for P3D.
Then I was introduced to ORBX.
And now FSX and P3D after adding ORBX Global, Vector, some OpenLC regions look totally 2019.
I have added couple of 3rd party planes and I am totally in love with my old hobby.
Whether ORBX, Lockheed Martin, A2A and others are in it for money or not - I do not care. I am just enjoying the stuff they deliver for the money :D