Why is the sporophyte generation dominant in vascular plants?

In the alternation of generations that characterizes the life cycle of plants, the sporophyte generation has become progressively dominant in vascular plants through the course of evolution.1

While bryophytes (such as mosses and liverworts) maintain a dominant, photosynthetically independent gametophyte generation, vascular plants have shifted this dominance to the sporophyte. This transition is linked to the development of complex vascular systems and specialized structures like stems, roots, and leaves, which allow the sporophyte to grow larger and more efficiently than the gametophyte.123

In most vascular plants, the gametophyte is reduced and dependent on the sporophyte, whereas the sporophyte is the conspicuous, long-lived, and independent plant body typically observed in nature. This evolutionary trend toward a dominant sporophyte phase provided plants with greater structural complexity and the ability to adapt to diverse environments.3214