[WA]

That is only half-true. On the one hand, I agree and I would never build a serious business on another single entity. But on the other hand, OP built an app that ran successfully for 10 years, generating some revenue.

Most products have an expected expiration date and you can provide a useful service (that generates revenue) by building on other platforms, even if it won't last forever.

By now I missed more opportunities by having the mindset of "not relying on other people's APIs" than real changes/shutdowns would warrant this kind of caution.