I don't think even Google actually
encouraged people to discuss politics at work. They never did when I was there. It was more a side-effect of decentralising the power to create forums. Anyone could create discussion lists there without asking permission, this was highly useful for coordination, making it easy to spin up new projects and avoiding siloing of information into people's private mail accounts. The flip side was nothing stopped anyone creating lists to discuss whatever divisive topics they wanted.
There's also been a cultural shift over time. When I first joined Google I remember feeling that it was a pretty libertarian sort of place. In my team several colleagues were openly and proudly very pro-capitalist, anti-communist, small government types. If anyone was left wing it wasn't visible and I don't recall encountering identity politics, ever. There was a very strong cultural commitment to neutrally serving every user with every query, and ranking being completely algorithmic, to the extent that the company agonised over hot-patching "Googlewhacks" where pranksters manipulated results for unusual searches to offend their ideological opponents.
This didn't seem strange, it was just how it was. I have a vague feeling I thought other tech firms were the same. Twitter declared they were the free speech wing of the free speech party after all, and anything internet or web related had a strong vibe of "communication will make us stronger".
This is a very far cry from the modern Google where arguing maybe girls find geeky stuff boring gets you fired, where they manipulate ML models to believe the world is some intersectional 'utopia' as part of social engineering programmes, where employees spend huge amounts of time erasing gendered pronouns from source code comments.
I suspect the shift was caused by Google running out of experienced software engineers to hire, and switching to growing through recruiting new college grads at much greater numbers. The hard shift leftwards in academic institutions has been well documented. Even in 2006 I remember a recruiter telling me they'd "run out" of candidates in the USA and that's why they were expanding more into Europe. The concept you could "run out" of candidates in a place as big as America was pretty shocking to me - on probing, he explained that almost all people with the skills they needed were in well paid happy jobs already and few were interested in moving, even with the great perks on offer. Whilst there were always a small flow of people coming onto the market due to natural churn, "everyone who cares knows Google is hiring" he said, and they'd already interviewed vast numbers of them.
This change in culture would inevitably lead to this situation due to the way that conservatives see leftists as naive, but leftists see conservatives as evil. Combined with leftists generally understanding conservatives much worse than the other way around (this has been shown by large scale ITTs), and together it means flooding your firm with new grads is a surefire way to create massive internal conflicts.