I don't think it will get rid of those matchups entirely. If the reports are accurate, the Big10 and Pac12 will go from 9 conference games to 8. All three conferences will require every team play a game against the other two conferences. ND will count as an cross-conference game. The article didn't say, but I would assume that ND would also count as an ACC cross-conference game. That would get all three of the conferences with 8 conference games and 2 additional P4 games, for 10 games total. That would leave 2 games that would most likely be like the NIU/KSU games. The article didn't have any speculation about the ACC/SEC rivalry games, but those will probably also have to count as a cross-conference game. If they don't then GT, FSU, Clemson, and Louisville would all be required to play 11 P4 games while probably no other team would.
Another word about marketing language and fan talk. The Pac12 and Big10 fans have been complaining for a long time that the ACC and SEC do not play 9 conference games, so schedules are not fair. The ACC has required an additional P5 game, so there was a requirement in place that each ACC team had to play the same number of required P5 games as those two conferences. GT's stated policy has been in addition to 8 ACC games and the mutt game to schedule 1 FCS, 1 G5 and 1 additional P5 team. Didn't always work out when the ACC and SEC cleared schedules for planned 9 conference games in their respective conferences. 8 conference games plus 1 additional P5 is no different than 9 conference games from a difficulty perspective. Most of the Big10, Pac12, and ACC teams scheduled 1 additional P5 game anyway for a total of 10.
The schedules won't really be much different under the reports about the alliance agreement. It will still be 10 P4 games. It will just be structured to get a more structured and distributed rotation for the OOC games. It will also just about eliminate OOC games for the SEC except for the four rivalry games. I think there would still be some possibility that the SEC would pull out of those rivalry games in that scenario. Except for the USCe/Clemson game, winning those games wouldn't mean much for the conference hype. Being swept in those four games would look extremely bad if they are the only OOC comparisons for the entire conference.