How is Ads using Flutter? It likely doesn't, or uses it for some largely irrelevant things like mobile SDK integrations
Wasn't it Analytics which had Dart? But I do remember something about Ads saving it.
> they weren't into doing yet another rewrite.
It all depends on politics within the company. For example: youtube was hastily rewritten using alpha/beta versions of Polymer targeting Custom Elements v0. The moment they did that v0 was deprecated.
So within next 4 years they rewrote Youtube again with Polymer version targeting Custom Elements v1. The moment they did that, Polymer was deprecated and replaced with lit.
Even though they haven't rewritten Youtube, they've now spent time integrating Wiz, an internal Google framework (that also got merged with Angular).
The costs of rewrites don't matter at Google as much as promotions.
You have to look at what teams at Google are using Flutter. Any dev tool Google officially releases tends to be funded by some product that actually likes/uses it.
Current list from https://flutter.dev/showcase: GPay, Earth, Ads (this is a big one), and others.
There are a lot of teams using it, which is why it's still getting so much support. If you see Google apps moving away from it, then it's time to start looking for an alternative.
It's also why AngularDart still exists and is getting updated. There are large projects that use it, so they will keep supporting it.