When architects were Master Builders, they were responsible for an entire project, from beginning to end. Over the years, as buildings became more complex, the architect became the leader of a team of professionals, a Master Builder by committee. However, along the way, a number of things fell aside, leaving others to take on essential functions that apparently were no longer important to the team. The first of these was extensive knowledge of building materials and construction, encouraged by the separation of architecture into separate fields of design and construction.
Since then, architects seem to have less interest in - or less time to address - other things, such as complete design, site services, and estimating. Yes, many architects provide some of those services, and some do better than others, but some have simply allowed others to take them on. And some project delivery systems have reduced the architect's role whether they liked it or not.
Why are architects not fighting to keep these lost services, and allowing others to take more control? Perhaps they are not willing or able to accept the associated risk.