I don’t think any game company is linear as you explain here... maybe in a very general summary... I am sure they already have planned the content, and why dlc they gonna have... etc etc.. it is true that the more time it pass, the cost will increase because they have to pay for all the workers. At least most of the content. But they might cut part of the initial content during the development. I studied programming, and I know a little know some of the develop way they follow... so when close to the death line of delivering the “final” product, they will just have to cut the content. 90+% is planning, 1-3% developing, and the rest is fixing bug probably.... specially now that most big companies have their game engine and all the library that they can use...