Everything about this is wrong.

1) The platforms aren't growing that impressively. Most of their users have been on the platform for a while, were previous users, etc.

2) It doesn't matter how good the app is, you need a network effect. New users are going to go to where the potential dates are.

3) Marketing does wonders. An app can suck and have great marketing. It will get users over an app that actually works and doesn't have good marketing.

4) Lots of people on dating apps are looking for dates (hookups), not partners. If the apps can keep you getting dates, not partners, they can keep you on the app and happy.