I already said that it's not a scam, but incompetence.
And yes, you can't just compare budgets, but you can compare polishing and production values. Undertale is far from the production values of The Witcher. I don't think that right now, the production value of SC is higher than TW3.
Well, right now SC is not even halfway completed. Even right now though you can do things in SC that you can't in any other game. The physics engine is a marvel and that's the main point of a space sim. Again they are surely waaay too inefficient and have lost tons of time with changing engines and completely reworking major features in the game. And that is some thing an experienced developer should not have allowed to happen. But there's a reason why noone has done anything like it before. It truly is a ton of work and it simply takes a lot of time.
Not even halfway completed... So, it should take around 15 years and 400-500 millions in total to finish the game?
Of course no one would ever finance something like this. It would need to be one of the most successful games in history to break even, and it surely won't be. The only way such a fantasy (yeah, developer fantasy, not business project) can be done is because of naive players who paid thousands of dollars for that. It's sad, honestly.
It's just a textbook example of mismanagement, and why you need people with a little business sense in a company. Creative people are usually terrible when money is involved.
Elon Musk has a bit of the same issues with Tesla, he decided to organize the factories his own way instead of following the usual methodologies, and the results are terrible, but it just makes him want to do it his way even more. You have people who are specialist in management (factory, development...), there is a reason for that.