They just built a 93,000 ft² training facility in Shanghai to develop new talent in Asia. It's three times the size of the performance institute in Vegas. So yes, they are spending millions on international development.
https://amp.scmp.com/sport/martial-.../ufc-performance-institute-shanghai-take-look
And a broadcast deal is meaningless If no one in that market knows what your sport is, who the stars are, how it works, what the rules are, or why they should care. You don't just "get" a broadcast deal.
Also regulatory work needs to be done in places you're not planning on holding a card anytime soon. The UFC spend a decade trying to break into New York They had to grease every palm in the state senate and even then they had to wait for one of their primary hurdles to disappear in a scandal. How much easier and less expensive do you imagine it is doing it on a national level in other countries or you don't even know the rules of the road.
Lastly Mexico's doing all right. They just crowned the first ever Mexican born champ who met with the president of Mexico. So I'd say their past investments are paying some pretty decent dividends at the moment. You can't ask for a whole lot more than a photo op with the president holding the belt. With some luck, a few title defenses, continued marketing, and the right broadcast partner you could see Mexico becoming a real talent and consumer market in coming years.
https://ouresquina.com/2021/champ-brandon-moreno-opens-mexico-for-ufc/
Time will tell with all of these things because the UFC is hundreds of regional champions and decades behind boxing in recognition.