True - the deal values UFC at around $12 billion, about $3bn more than it does WWE and a near trebling of what it was valued via the deal to buy the controlling stake in 2016. So clearly Endeavour are not going to be in the market for changing a formula with the UFC which they will see as currently being very successful.
That being said this isn't a shrug of the shoulders and everything goes on as normal deal - there are a bunch of ways they could have done this that didn't involve merging the UFC into a combined and separately traded company with WWE. The manner of this suggests that they see, in dreaded corporate speak, 'synergies' between the two businesses that could see both benefit from being operated by the same company.
It's quite a momentous thing and while its not about to have UFC fighters with supernatural gimmicks or triple threat matches, it will very quickly have an impact on things like pipeline of talent, cross-promotion, third party contracts and more.