Latest production equipment and software.
ESPN has been paying Big 12 schools cost plus to produce ESPN plus content. Many Big 12 schools are investing in their own equipment like BYU. They are maintaining it and it is cheaper for ESPN to lease it for Tier 1 and 2 games.
Conference networks, including the BTN, are losing subscriptions and since the live content aired typically isn’t the type that draws high ratings, the ad buys have a ceiling. It’s a bit like investing in music CD production in 2003. Just because it is cheap now, doesn’t mean it will be profitable long term. The ACC deal also takes up valuable east coast slots ESPN could get greater viewership with using SEC content. Viewership and the related ad buys are what is valued which means premium content needs to be produced to generate premium profits.