I don't think the UFC will go down however I expect it to got through a rough patch in the next 5 years with the new owners. It really depends if during that rough patch if any big UFC fighters decide to jump ship to Bellator or WSOF etc...
Just like nobody believe PRIDE Fc will go down, 2017 will be tough for UFC if Conor will lose and same with Sage.
I just want to see competition, sometimes i feel to drink Pepsi and sometimes Coca Cola, only problem is that everyone thinks Pepsi is less better because they are not popular, i do like Pepsi Max