Just because technology moves faster and gets better that doesn't neccesarily means everything is getting easier. Sure, a lot of things to but with new changes new challenges also arise because development constant evolves as the time goes.
Here is what a typical development cycle looks like.
1st - There is the idea phase, where the team comes up with a gameplay loop, prototypes and core mechanics and identify what the genre of the game is. This as you can imagine takes time, because the oubmishers also need to approve the idea because at the end of the day it needs to sell and make $$$. This is a business first and foremost.
2nd - During the idea phase assuming that it does get approved what happens is that the team creates something called a Design Document, yes litterly a document that explains every single mechanics, how it works, what it does and what it's for.
This is a document that everyone refers to on the team, including the programmers and artists because the document includes the theme of the game, artistic visuals and of course for the programmers the core mechanics and they need to understand it so they can code for it. Think of it as a blueprint.
We did this in a university but as you can imagine we had no budget and we only had 3 or 4 months to create a game but the cycle was exactly the same just on a much much smaller scale.
2nd -After the design document is done then production begins. Artist usually have an art director and programmers have their main technical guy that oversees everything else as well. But the art director and programmers director also have a production manager that oversees them. I was an artist on the team, I did 3D modeling which is where you create 3D models for video games as assets and I was prop artist meaning I created 3d models such as weapons, small objects, gadgets and things like that. 3D modeling would be done in Maya or 3ds Max. Cresting 3D models I'd not easy, especially at a high pro level because you have to optimize the triangular count for game engines or otherwise your game will run like shit and your programmers will come and kill you in your sleep for making things difficult for them than it needs to be. Then i also had to do textured which photoshop. Thankfully our game was cartoony so our artstyle was all hand painted in photoshop using wacom tablets.
These models are then given to other people and are imported to game engine and then you have animators who also animate these assets.
Here is an example of a very complex high quality model from Guerulla Games artist. To do something like this constinetly takes years of practice, tons of talent, skill and basically be a master. Bow imagine pumping out models like thisbat a fast pace with high quality in weekly basis.
Long story short, high quality stuff at a very high level take a lot a lot of personal talent and skill both on programming and artist end. These things are very difficult, and when you throw millions and millions of dollars for big AAA 1st party title it then the final product needs to deliver and perform well both in sales and critical acclaim and to do that properly it takes a very long time.
I could go far into more depth but that would take a while to explain. But this should give you an understanding. I didn't even really talk about the half of it.