They are a commercial company, so they obviously budget out the different departments that work on the product.
Just because something is open-source does not mean you can reduce your amount of software engineers. Even if the community contributes a lot, you have a significant increase of PRs that need to be approved by your own people. However this is not the case for Snapmaker. Just looking at their Luban repository, by far the most commits over the last year were made by Snapmaker employees. So the open-source argument is not very strong.
Of course I cannot prove anything on paper as I do not have insight in Snapmakers financial record. Looking at the software they have available on GitHub: again it’s serviceable but not at the same quality level as their hardware. For sure they could spend big and pull open a can of software engineers and make Luban better than anything else in the market, but they don’t.
Ideally, the Luban integration should be top-notch so no one even needs to look at third-party solutions. It’s not exactly rocket science, as just adding proper multi-pass support would make a world of difference. They don’t even need to spend time figuring out the details, customers already did it for them nearly 3 years ago: Multi-Pass Rotary Guide.