What factors determine why these are the most used materials?

For residences, wood structural materials are commonly used. This is because the technique for wood framing is widely known, the units of construction (i.e., studs, joists, panels, etc.) are small and easily transportable, and wood-framed structures do not require special tools to put together (source: )

Office buildings are more likely to use concrete and steel for their greater compressive and tensile force capacities that are necessary for much taller buildings. These two conjoined properties of compressive and tensile resistance as well as the relative ease of their production and ultimate construction has made them ideal materials for mass production of large scale buildings. There is newer interest in wood materials in the mass timber movement dedicated towards finding a potentially more sustainable alternative to steal and concrete for tall building construction. 5 common structural framing systems are Braced Frame, Rigid Frame, Wall Frame, Sheer Wall, and Core Wall Outrigger (source: https://www.constructionexec.com/article/five-types-of-structural-systems-in-high-rise-buildings). The application of the different systems appear to depend on the exact materials on hand (primary concrete or primarily steel) as well as the design specifics of the building (does it have a cantilever, might it benefit from the side effects of acoustic dampening from a particular system, etc).

What are the advantages of linking models?

Are there any disadvantages to linking models?

What advantages does doing this coordination digitally have over previous methods?

Likely plans and sections were some of the greatest tools along with a carefully put together physical model. However, physical models can be tedious to build and in the earlier centuries when a cathedral took centuries to build perhaps that was acceptable but by today's standards waiting for an accurate physical model that can help coordinate work is likely quite a hassle and drain on project budgets. Similarly, plans and sections, drawn to accuracy needed, take time and still often contain mistakes that do not automatically highlight themselves to the project team. Thus, the digital coordination method provides these important abilities to notice clashes and issues that are easily missed in a sea of plans, sections, and the details they contain while saving time that these traditional means of representation would have eaten up.

What can be done besides sharing the models digitally?

Is it ever too early?

Coordination should start after the fundamental wants and needs of the project stakeholders are voiced. This is to ensure the creative process is not hindered by the current restrictions of technology, legal liability concerns, etc. Once these ideas are given physical form through concept drawings and the like, then the project may benefit from other voices entering the ring. For example, if you have a client who wants to feel like they are floating in the clouds in their home and the architect proposes making glass stilts, it would be beneficial to have the structural engineers explain how difficult that would be but not allow them to say no to the goal of feeling like they are floating on clouds. As the design process continues, the consultant/advisory role of people like the structural engineer, hydrologists, etc expands to one of designing and integrating fields of design and engineering, allowing more control and authority to be handed to the people who need to make the dream reality. In this way, an early design decision that would be absolutely impossible to make happen can stay in the realm of early design rather than continuing to the point of demanding unnecessary costs to either roll it back or make it happen at all costs