To answer your question, you have to dive a bit deeper. A company/brand choses a color for various reason, one can be industry(which you rightly identified), it can be perception, but most importantly it has a lot to do with branding.
Company likes to stick to a color for both internal and external communication and representation.
Sticking to one color helps connects with user. Imagine a coke red, you see on any platform and you will say its coke. Brands use color, unique fonts and unique design elements to constantly bombard and indirectly promote their identity.
Brands even go to the length of making their own font so that they can promote an identity in every communication and user can by instinct know which brand is in the communication.
I think you should start your journey from the logo the company has, and then make a design system that takes into consideration of the brand guidelines(assuming its in progress) that exists and build on that. If it doesnt exist then you should research and do some usability testing on what color connects with the user most for the specific type of social media you are planning to make.
Personally the color will not affect the user much but the balance of what color you use varies by color. So a blue can be used more frequently but a red has a differnt affect on the eye, and hence should be used cautiously.