Last year 0 EFC students with Presidential Achievement scholarship most likely had exceptional class rank, grades and test scores. It is pretty common that UT gives students like this financial aid better than ivies do.
A couple of years ago I talked to a guy who was in top 6% of his very noncompetitive Texas school with some Cs and SAT below UT average. He was accepted to UT Austin as an UGS student. His EFC was very low, not exactly 0, but not much above it, and he got Pell grant and loans only. His family declined the offer, and the guy went to community college where he struggled with Math and Physics classes and changed his mind about being an engineer. When I talked to him he told me that it was good he did not go to UT Austin, he would most likely drop out with loan payments due almost immediately. He told me he felt lucky he did not make a big mistake.
EFC 0 alone doesn’t entitle you to a lot of financial aid.
EFC 0 + exceptional academic ability (way above average EFC 0 student) usually do.
Need based UT scholarships are also merit based ( ALWAYS ), and they serve as recruitment tool to attract students that UT really wants. Really, really wants.