Ive tried to educate people on this for over a decade, but people want to think the tin foil hat is just a theory. ESPN/ABC/Disney has both the SEC and ACC contracts. For the past 10 - 12 years, the ACC has officiated games with the intent of creating the following outcomes.
1) A Singular lion. It's typically been Clemson or FSU.
2) Bowl-eligible parity among all of the other teams.
They do not want the ACC to be seen as a powerful football conference. That's not what Disney wants. ACC viewership is dwarfed by SEC viewership. The last thing Disney wants is the ACC having four teams in the playoff, especially if they're beating SEC teams.