Paying off politicians has worked well for Google since the Obama era, but it's not working anymore. Reason why was Trump's election. Politicians realized that Google's services, and how they're moderated, can do a lot more to affect an election than a donation ever could.
You have a point there... but even so - Google has been censoring non-mainstream political views, and artificially promoting mainstream news media (the big networks anyway). Isn't that enough to curry favor?
Not really. Perception is everything. Democrats believe Google allowed Trump to be elected by valuing profit on platforms like YouTube rather than intervening in extremism. Republicans believe Google and it's largely liberal-leaning employees are censoring conservative voices via algorithm updates and deplatforming.
The truth is probably both are right in certain respects, and so Google finds itself now without many friends in the political sphere.