The brokered convention could be a double-edged sword.
That's okay. A "brokered convention" in the classic meaning of the term, is unlikely to happen, for one simple reason - lack of leverage.
What we think of as "primaries" started in 1972. Before that time, all conventions were brokered. State delegations to the convention were chosen by the state political parties. So, the people who went to the convention were, in some way, beholden to the state party, and usually to the 'machine' politician that ran the party (think Mayor Daly, and Tammany Hall). The people who were sent had a connection to a person who had power to give favors to them afterwards, and so there was a path of influence from the main party bigwigs, to the local bigwigs, to the delegates - a kind of web of patronage, and brokering could happen. So long as the delegate followed orders, they could expect nice things when they went home, because whatever happened in the national election, the *local* party apparatus at home lived on.
Today, instead, the party decides how many delegates each state can send to the convention. A few of these delegates are "unpledged", can vote for who they want, and are usually current or former elected officials or high ranking party members. Most of them are chosen in the primary election - when you vote in a primary, you are, in essence, voting to send a delegate from your candidate's *campaign* apparatus. For these, there is no solid chain of loyalty to the party apparatus as a whole. These pledged delegates must vote for their candidate in the first round. If nobody wins that first round, they can vote for whoever they want.
And, of course, if the delegate's candidate doesn't win... well, that candidate is by no means guaranteed to be in a position to be a patron, or fulfill favors in the future. The apparatus they are connected to will not live past the election. There's no clear path of influence to the delegate at that point - the delegates are almost all free agents, and in order to influence them, the party apparatus would have to negotiate with them individually, which isn't tractable.