Essentially, Instructional Design is identifying a problem, establishing a learning goal(s) that explains what said learners will be able to do after completion, creating objectives that aid the learner in working towards the goal, and establishing the norms/environment in which the learning will take place. This is educational psychology at its finest. ID is a process of apply instructional theory to practice.

As in Educational Psychology, Instructional Design examines learners in the classroom via needs assessment, learning environment, and learner analysis. These analysis provide the data and information necessary to appropriately and adequately inform how instruction should take place in an effort to increase learners skill and knowledge.

While Educational Psychology and Instructional Design are ideal in their intent there are always limitations to effectiveness. In my opinion the greatest limitation for this learning science is the implementation on a large scale. On a small scale (i.e. classroom level) implementation of new programs and training is feasible, but on a macro level (state or federal levels) implementation becomes delayed due to legislation, access to equitable resources, and the sustainability of the new programs. A crucial factor that science can't account for is diversity and inclusion.

Dick, W. (1987). A history of instructional design and its impact on educational psychology. In Historical foundations of educational psychology (pp. 183-202). Springer, Boston, MA.

https://www.scientificworldinfo.com/2019/04/application-of-educational-psychology-in-teaching-and-learning.html