That's ok. If this plan works, a few years down the road Ublock will get dropped/disabled for you under some pretense when Google can claim they've got you covered for "ad blocking".
You're thinking far too 1984 when the answer is much more Brave New World - if the ad blocker in Chrome is good enough, people will just stop supporting UBlock.
Naw, Google has precedent for this sort of behavior, going so far as removing plugins from their web store and quietly uninstalling them from Chrome with no notification when the plugin interfered with their business model. They actively uninstalled video download plugins without notification to the user a couple years back. Nefarious.
I think you are severely misunderstanding the situation. Google can do whatever they want. They've already demonstrated that they have no problem installing things on your computer that you never would have otherwise agreed to. That, and they don't take no for an answer with updates.
Do they? I just downgraded Chrome for Android to 56, because the latest one would crash when playing live video streams. Granted, Play Store didn't have that option, so I had to download the APK from a third-party site and disable automatic updates for it, but nothing prevented me from doing either thing.
Yes, it's possible—I would say probable—that after introducing their "impartial" ad blocker, whose rules for acceptable ads just so happen to allow all of their ads through, and after enabling it by default on their browser, they will actively block all other ad blockers, on "privacy and security" grounds.
If, by any chance, someone decide that its browser is already covered as far as adblockering goes, we will simply move to a different browser/adblocker/adblocking solution.
As long as there is tech savy people there will be plenty of solutions around.