Competition was always doomed to end in the way it used to exist, for the simple reason that shareholder profit is considered (by law, even!) the sole purpose of a publicly traded company. For X company, having a monopoly on something is always going to be better than competing against Y company, and vice versa. So what happens is a kind of unspoken agreement between these corporations: X company will not attempt to compete with Y company in area A, and Y company won't try to compete with X company in area B. The was done most fervently with telecommunications companies for a long time, but an easier to understand example would be Microsoft allowing Xbox exclusives like Cuphead to be sold on the Nintendo eshop, because the way Microsoft sees it, they don't compete with Nintendo. This sort of thing is being done to a more and more extreme extent across just about all financial field - large companies simply agree not to compete, allowing for soft monopolies to form within specific sub-sectors of a market. Any smaller companies or start up that attempt to disturb this balance are ruthlessly crushed, which is much easier now that smaller companies can't leverage competition between large companies to create a niche for themselves.
TL;DR Finance is gradually reaching a point where major corporations simply won't tolerate competition anymore. It's much easier just to create multiple soft monopolies within specific market niches and agree not to interfere with the soft monopolies of your supposed competitors as long as they don't interfere with yours.