Why not? When the election is making their company have a difficult time becoming a more successful work place? I think it's a company, people can say what they like, if Google doesn't like it as a whole, they can fire said employee.
The purpose is Google's company wide meetings with the executives is not for the Executives to complain, but for the employees to complain and the executives to respond with a plan of action.
In the meeting in question, employees were asking Google how they're going to help stranded employees, how Google is going to protect them, how they can still travel outside the US if their job requires it (e.g. You're a British/Iranian citizen)
Google executives did not get up on stage and given an anti-Trump rant. In fact, as far as I recall, they've never directly insulted Trump the way you can see in major news media, because who wants to make an enemy of the US government and what use would it be to give a political speech? What they did is respond to the concerns of employees, and some of them are immigrants, and got a little choked up with emotion in their voice, because they were shocked too.
My extended family has a lot of first generation immigrants. None of them understand American racism and xenophobia like a native, and they thought it was just focused on Mexicans. The travel bans were the first hammer, the attacks on legal immigration (greencards and bringing family members), Bannon's "There's too many Asian CEOS" hail back to the attitudes of the Chinese exclusion act, and finally Charlottesville, all show the danger of playing around with xenophobia. It doesn't stay contained the way you think, and many educated, elite immigrants were suddenly shocked that they might be affected too.
Nobody is arguing Google's right to express political opinions, but the fact that their culture does so is counterproductive to a meritocratic structure. They seem to be more concerned about virtue signalling than creating an environment that focuses on professional and economic growth.
It's like the culture was shaped by having a "Don't Be Evil" motto or something.
(Also, it's interesting that you separate politics and meritocratic structure. It is by politics that the things that are merit-worthy are decided---you can be the best developer in the world, but if you're developing the wrong thing, you're not adding value).
