Other sports (mostly outside of the U.S.) feature competitions that are fairly equivalent to Festival of Champions.
In much of Latin America, soccer seasons are divided on the calendar into two separate halves, each with their own champion. In a few of these countries, the two half-season champions play each other to decide the overall champion that year. In other countries (like Mexico), the two half-season champions play each other in a standalone tournament, but both participants are still champions of their respective season.
Likewise, in European soccer there are several simultaneous orthogonal competitions in each country that each crown their respective champions and then begin the next year with a Super Cup. In general, winning a Super Cup means you get an official trophy and some bragging rights, but it generally carries less prestige than winning the competition that got you there. I think this is the right framework for thinking about Festival of Champions.
Lastly, even as an outspoken critic of Two Champs, I don’t have any difficulty recognizing all 8 STL/Houston teams as World Champions. There are ~3350 teams in FRC now and we crown 8 champions. That’s about the same rate of champions per registered team as in 2007 (3 champs for 1305 teams). Are we going to start saying that Championships in the alliance era before 2007 don’t count? 
