The jury is still out on UCF's overall competitiveness in the Big 12. This last season was not good for UCF athletics: 14th/15 in baseball, 14/16 in men's basketball, 13/16 in women's basketball, 15/16 in football, 13/16 in women's soccer, 7/11 in softball, 14/15 in volleyball, T14/16 in men's golf, 9/14 in women's golf.
I think people underestimate how long and how much investment it takes for an athletic department to develop programs that are competitive. UCF invested in football to get the P4 invite and it paid off, but their other sports weren't ready for the move as they weren't that competitive before they moved to the B12. And, UCF is the big outlier in the Big 12 with the nearest conference schools about 900 miles away.