Just look at the state of Android. Try being a cell phone OEM who wants to use Android but without Google integration. Impossible.
Tell that to Vivo, Oppo, Honor, Huawei, Xiaomi, Meizu, OnePlus, Lenovo, Qiku, Smartisan, Amazon, etc.
Not in China. Some of them have an "International ROM" with play store, but not because they have to, just for non-Chinese users convenience.
- Auto sign in and the "Google account indicator": this is almost certainly the result of discussions between the Chrome security team (security indicators, phishing, etc) and Google UX requests. Heck, they even say that the indicator was motivated by user research around session management.
- Tracking: I'm not sure what extra tracking was added to Chrome beyond the existing telemetry they've had since the beginning of the project.
- Google cookies: explained above - a reasonable idea at some manager or UX designer's local scope that got misinterpreted.
If they really wanted to sneak in goodies to supercharge their ad business, it would look a lot worse (and be a lot less obvious) than this. For instance, there's nothing stopping them* from automatically enabling Chrome Sync and removing the option for encrypted syncs tomorrow... which is another issue, but a different scope of discussion.
* Aside from their entire legal department, of course.