The answer to this question is largely debateable and open to opinion. The simple answer to this question is yes. Students who are likely to need alternate educational approaches typically experience more success in school if their needs are caught and acted upon early.
That said, this question is "loaded" with two controversial topics which I encourage you to bring up with your class. The first potential controversy here is the definition of "minorities" within the question. Likely, this narrowing of the field of study is due to statistics that minority students have lower academic achievement, generally speaking, in American public schools. That said, when addressing the topic of educational needs for students with an ADHD diagnosis, there should be no discrimination between white students and minority students. ADHD affects individuals differently, but is not affected by race, socio-economic status, or primary language barriers.
The second potentially controversial subject here is the diagnosis of Attention Deficit Hyperactivity Disorder. There are those who believe that the "diagnosis" for this is streamlined and somewhat inconclusive, at best, and highly overused at worst. Many students who have perfectly normal brain function have different physical and emotional needs, and simply have a more difficult time assimilating to a traditional classroom that is focused on sitting still and teaching to a standardized test. Many students are medicated in order to succeed in this environment that is not built around their learning method. In this case, "early intervention" might mean a number of things, medication not excluded. Early intervention with the school system also likely means conducting an IEP meeting, documenting alternative strategies to the mainstream methods of education, and essentially, a trail of paperwork that will follow the student through high school.
With that in mind, parents and educators often question if traditional early intervention really is best. A hyperactive Kindergartener, for example, may grow out of some of the physical needs he has within a few years. However, if strategies are implemented early, this student will carry a label into future grades, even if the intervention strategies are no longer needed. Conversely, a successful Kindergarten classroom and teacher are intervening on behalf of the melting pot of learning styles present at such young ages, and reaching as many students as possible through as many learning avenues as possible. Montessori School is a great example of an alternative educational approach that caters to the physical and spatial needs of perfectly normal young children.
I encourage you to bring these ideas up by considering what is the issue at hand? Increasing academic success in minority students, or increasing academic success in students who have been diagnosed with ADHD? Consider that learning differences at early ages do not necessarily mean there is a learning disability present. If "early intervention" means more standardized tests, documentation, and individualized education plans, I am personally on the side that this could be equally detrimental as helpful. If "early intervention" actually meant classrooms that are dynamic, implement strategies that reach as many learning styles as possible, and provide individual support to eachstudent (not simply those potentially labeled "at risk") then, yes, all students would benefit from early intervention in order to be set up for future success.