The Big 12 media contract extension begins in the 2025/2026 season which is this year. Bottom line is that starting this year, the ACC and Big 12 conference payouts will be similar, but the ACCN revenues gives the ACC a slight edge in total payout.
Also the Big 12 will be on multiple networks. Beginning in 2025, the Big 12 will have three linear television options for its football inventory (ESPN, FOX, TNT) and four networks for basketball (ESPN, FOX, TNT, and CBS). Beginning in 2025, TNT will broadcast 13 football games and 15 basketball games that previously would have been on ESPN+.
This season is 2024-2025. You are saying Big XII's payout next season (2025-2026) will be comparable to the ACC's payout last season (2023-2024). But there will be two years of elevated payments for the ACC and whatever the ACCN churns out with California and Texas footprints in-between.
No one is moving conferences so they can get on TNT, so that's just a big shrug.