You've weirdly conflated 'academic potential' with 'future careers in academia'. Academic potential means the ability to learn and contribute to the undergrad environment in any given third level environment.
Financial aid has always been need based.
Merit scholarships have always been a completely different kettle of fish.
(Assuming you're talking about the past three decades - back in the days of making enough at your summer job to afford private university, things may have been different).
Currently, students can get financial aid in varying proportions from the university that admits them (you apply each yearbfor financialnaid, via the FAFSA alone for state universities and via FAFSA plus CSS Profile for private institutions) plus scholarships for any kind of attribute they may qualify for - e.g. young woman from a large family seeking to major in mathematics, student whose ancestors come from a certain town in Greece, etc. Quite often, but not always, a scholarship needs to be declared, and the financial aid offered by the institution is reduced by the amount of the scholarship.
On top of financial aid (often offered as part of the package) there are federally subsidised loans, up to a limited amount and repayable after graduation, and Pell grants, which are paid to the student and are not loans (again, limited amounts available per student). There are also education loans that parents can take out, repayable upon disbursement.
There are thousands of students in the US who have long lists of fantastic attainments in the fine and performing arts, sports, community leadership, entrepreneurship, and more, who get turned down by elite colleges and universities every year. Admission to these institutions, which attract tens of thousands more applications each year than there are places available, is basically a crapshoot, and there is no way to tell what criteria in an application an admissions committee will accept or reject.
Priorities of an admissions committee can include increasing representation in the student body of rural applicants from mountain states, increasing representation of students from small southern cities, and pretty much any other category you can imagine, barring categories recently deemed unconstitutional.