That is and will always be the nature of combat sports. No promoter of fighter could change that. It'd be up to us as fans, to tune in for all fights regardless and that will never happen.
there are a few reasons this is a bad comparison, the first and major being production costs. All of those leagues pay zero in production it's covered by the networks while the ufc picks up all of that tab. Not to mention how crazy priced the insurance coverage would have to cost for combat sports, that the ufc and no other promoter offer, as well as the highest level of drug testing in any of those leagues. Which would also be huge financial burden. Also add in the mass amount of money spent in the last decade fighting to get mma legalized and global expansion. Hell mma was illegal in my state until recent. Now while we don't know what percentage of revenue the ufc pays out with any degree of certainty any kind of comparison doesn't hold up.
I think you are over estimating how much value a title actually brings to a fighter. There are plenty of instances where champs are making less then other people in there divisions, which are totally justifiable. As much as we like to think these guys are paid to fight, the truth is they are paid to generate ppv $ and tv viewership which in turn equals advertising revenue. It's how the ufc makes their money so its how they dish it out to their fighters. The NFL doesn't make 13 billion a year because they are great athletes they NFL makes that much because they are the most watched thing on television and generate a ton of advertising money. If their viewership goes down so will their pay. MMA is too volatile a sport for that to be level across the board, some guys generate some guys don't. Rewarding the guys who don't figure out how to do so only hurts the guys who do. Who would in turn go somewhere that would pay them what they are worth.
You and I are in the same state and city and I think we both know getting MMA here was symbolic more than anything and not indicative of the success or tenuousness of the sport.
We've been fed the same line about the volatility of the sport for decades and I just don't buy it anymore, particularly considering the recent sale, deep pockets of the new ownership and outside estimates that the UFC is one of the most valuable brands in sports today.
Saying that "is and always will be the nature of combat sports" just isn't reflective of the growth we've seen over the past several years in what was once a very niche market. Also, while the UFC shoulders all production costs, we don't know how much of their revenue that accounts for. We do know there have been offers made to take over production and they've turned them down, preferring to keep control of their brand at all costs while denying fighters the ability to do the same. As far as the money they sunk in to expand the sport, we know they made that back in spades after the recent sale so how long do fighters have to wait to make their claim?
You make a good point that titles are inherently meaningless to drawing power, but that doesn't mean the legitimacy of the idea that it's an actual sport isn't undermined by the fact that there is no incentive to follow anything resembling a ranking system besides occasional (and arbitrary) promoter strongarming.
I do disagree with the fundamental premise that fighters are being paid to sell PPVs. That is the promoter's job. That's the main reason they've existed in all combat sports; to sell the fight. A fighter's job is to perform well, which maybe brings with it some obligations to be entertaining, but consists of winning first and foremost.
If their only job is to sell PPVs, there's nothing stopping a group of say 100 top fighters from going out and selling their labor to say ESPN or Fox Sports or even an online streaming service to shoulder the production burden where they and their managers do all the marketing themselves and then go fight. Except they're prohibited by restrictive contracts in all existing promotions from doing so.
The sport can evolve, in revenue sharing, promotion, and meritocracy, but fighters will ultimately have to force the issue. When that happens, a lot of people are likely to be unhappy, including the fan base, at least for a little while. My hope would be reform before that moment occurs, but at this point, it seems highly unlikely.