Back in those days, games were written in Assembly to get every last bit of performance out of a game because you needed to. Nowadays we could games in Java/C# for smaller, less ambitious things and C++ for big AAA titles. Both usually have some kind of interpreted language like LUA or Python to script the game. Give it a couple more years and we'll be doing with Java/C# what we needed C++ for today (it's already happening), and Python/Ruby type langauges for what we use Java/C# for today.
dev time must have been quite long
It was about the same, and games were much much simpler back then. Doom took about 1 year to make, which is par for the course for most games today using much more advanced technology.
A lot of the time and development that goes into a game is the assets. A single set of code is often applied to a wide variety of objects to define their behavior, but meshes need to be designed individually. Older games often took less time to make since the artists didn't have to make as much on the simpler hardware.
That doesn't mean that projects aren't ever programming-limited, however. Crysis 2's time in development (~3 years) was as much a factor of programming as it was of asset creation. It was released along with CryENGINE 3, driving the engine's development as well. Assassin's Creed and Call of Duty, on the other hand, have the 1-year development cycle since they reuse most of the code and assets for each iteration.
My point was that the raw development time of one game vs. that of another is meaningless; the development time in man-years is more meaningful. Both Doom and Dishonored (really good game, by the way) might have taken a year to make, but if one has a team of five people and one has a team of fifty, and one has a budget of $10,000 and one has a budget of $1,000,000, then it's not fair to compare in raw development time (yes, I did make those figures up, but it's besides the point).
What I have come to understand while starting my game and studying the process of other games is that usually for the big titles the majority of time is spent on the artistic side of things (Sounds, 3D graphics, 2D graphics, ect.). The same goes for the budget.
And what chris is saying is also true, it is very unfair to compare lets say a indie game title to a AAA game title. The indie game probably has 5 people working lets say 40 hours a week on it for lets say a year. Now the AAA game has lets say 50 people working 40 hours a week for a year
40 * 52 * 5 = 10,400 hours
40 * 52 * 50 = 104,000 hours
So like chrisname was saying you cant compare the overall development time of a game to another game. Because there are so many different variables. They both might take the same time to make but they also have different team sizes, tools, budget, ect.
They both has the same release time but one is putting in much more man hours then the other.