I was speaking more for a view on this season's ACC. I don't think what happened 4-5 years ago really matters at all to how you evaluate teams in a current season. But if you want to look more at the macro view of the ACC instead of the micro view of this season's ACC we can do that.
I'll keep it to the past 15-20 years or so, and I chose 2005 as the year to go off of since that was Miami's first year in the ACC. Results going much further beyond that don't hold much weight to me because programs and the game both have evolved so much. Jim Valvano and NC State beating Houston matters zero to how college basketball is run today.
UNC and Duke have dominated the tournament (under all-time great coaches) to rack up numbers for the ACC, but the rest of the ACC has not done much. Virginia has the title in 2019, but they've otherwise been regarded as chokers in the tournament under Bennett. Most of Louisville's or Syracuse's success came in the Big East or prior conferences (for Louisville) - those programs have fallen in stature since joining the ACC. At least Syracuse does have that one run to the Final Four as a 10 seed in 2016. But 2019 Virginia and 2016 Syracuse are the only non-UNC/Duke teams to make the Final Four from the ACC since Miami joined the conference.
Since 2005, the ACC has 11 Final Four appearances, but 9 of those are UNC/Duke. The ACC is right in line with the Big 10 (12), Big East (11), and SEC (10). The ACC does lead the way with 6 titles in that time frame, but once again, that is because UNC and Duke have 5 of them. The Big East has 4, the SEC/Big 12 have 3, and the Big Ten has the title drought.
But if you want to look at the depth of the league, the ACC has only placed four programs in the Final Four (UNC/Duke/Virginia/Syracuse) in that span. This is behind the Big East which had 6 and the Big Ten/SEC which both had 5, while matching the Big 12 with 4.
To me, that doesn't suggest the ACC is dominating. It tells me that UNC/Duke were dominating and stacked up numbers on behalf of the ACC.