I think that is going to be a big problem going into the SEC for OU, and to a lesser extent TX. You think those fans are going to be ok being relegated to Auburn most years? Hell no. Huge expectations in a much tougher environment.
How will the SEC be better for OU shorter term? More money certainly. Recruiting just got much harder. Most schools have more fertile recruiting grounds in their backyard and OU's current recruiting budget would be 7th-8th best in the SEC. Advantage in recruiting Texas kids (top school in Big12 and lots of games in TX) will greatly erode. Recruiting future HCs would be more difficult. OU in the SEC will be the 4th-6th best job in the conference compared to 1st or 2nd currently. On-field competition, that clearly got tougher too.
Until the SEC finally succeeds in creating a super league and multiple losses are expected by all teams annually, similar to the NFL, I think OU fans are going to be pretty unhappy with the new norm.