I don't see this as sufficient reason not to join a platform like Fabric. This could make it visible to a lot of developers who don't even know about deep linki

I don't see this as sufficient reason not to join a platform like Fabric. This could make it visible to a lot of developers who don't even know about deep linking, or that it can be done with an SDK. A big appeal of Fabric is also how easy it makes it to integrate kits into apps. You may be experienced enough to do the plumbing yourself, but the convenience Fabric brings lowers the bar to entry for many.