I strongly disagree. Google, like other companies, is very opportunistic and 100% calculating. Standing up for refugees and against Trump is a no-brainer move in Silicon Valley culture, especially when 1000s of others are doing the same and the majority of the media is on your side. There's only upside and no downside for Google and its employees in doing so.
Sergey could have easily used his connections to get a 1:1 conversation with the president. That would have been 1000x more effective than joining a demo at SFO. He still chose the latter because he knew the effect it would have on social media.
Google could use their resources and power to help with other causes and problems whose negative footprint on American society outclasses the refugee problem by orders of magnitude. But why waste any resources on that, since it's not a hot topic in the media and Google's hiring plans aren't affected? Nothing to gain there...
Meanwhile they're getting close and cuddly with Trump's party to secure their political backing [1].
I'm not pro-Trump, in fact I think his refugee ban is beyond crazy, however I'm very deeply suspicious of people / organizations who tout themselves as the good guys ("don't be evil!") and then only stick their head out of their comfort zone when the cause is no-risk and it's ensured that the world is watching.