Partition it geographically. If they want to compete in certain cities/regions/countries where the user base exceeds a certain number, they must spin off subsidiaries for that area. I can't imagine people looking for a date on the other end of the country outside of very specific circumstances.
Isn't this how we just end up in the same situation we have with ISPs? It doesn't matter that we have Comcast, Cox, and Charter if any given area only has one of them.
Building an ISP requires investing in infrastructure. A dating app needs a UX designer and a few cloud instances. There's a world of difference in the required outlay when building a competitor.
Geographic partition is what we did to Bell, and that really doesn't seem to have helped much. If the only way to choose a competitor is to move, there's still really no competition. No one spent thousands of dollars moving across the country because the telephone company there was better.
Weirdly enough that's what the US is doing with government on a state level. With people claiming that each state is an "experiment" even though the people there likely don't have a choice in the matter.
The difference is that state policies are so impactful in everyday life that people very much do choose where they're going to live based at least in part on state government decisions. The same cannot be said for most corporations you could conceivably split along the same lines.
Eh? Subsidiaries aren't usually what people mean when they speak of breaking up companies. Subsidiaries are aligned with the parent company in terms of incentives, so it doesn't really change the landscape at all, besides worsening the user experience if you require the subsidiary to maintain its own isolated silo of users and data.