It is in the end. But when comparing B12 and ACC, that's nearly a 25% increase. They are currently about the same in total conference distributions (read somewhere ACC presidents are thinking they will receive ~$43MM this year, B12 distributed $44MM last season). With the revenue increase from Calford/SMU (SMU's full share, plus Calford's fractional share), the bump in ACCN revenue from the two new states, plus the ~$1M/school payout more than B12 for CFP distribution, the B12 will need quite the bump for it to be "profitable" for an ACC school to leave for them. This does not include the ACC's "performance bonus" structure payout (we do not know what that looks like, how much, to who, what sports, etc.), plus any negotiated exit fees from FSU/Clemson when they settle. Could it happen? Sure, but doubt any move of ACC->B12 will happen until 2030 (pending next B12 contract) at the earliest barring a total implosion of the ACC before then.
Here is an estimated payout from a GaTech fan for ACC schools over the next few years for what it's worth (obv. grain of salt):