This is happening because these large tech companies- not just tier-1 unicorns but FAANGs themselves, have been presenting themselves as paternalistic employers for the past decade. You provide employees with all the free food, on-campus gyms, and massages by appointment as they want, then present them with supposedly open cultures of free inquiry, your employees are going to use it. You satiate someone's lower levels of Maslow's hierarchy, and they're going to want to self-actualize. So the freethinkers and activists motivated to join these companies are going to try to engage in activities beyond, well, work.
So the companies reaped what they sowed. They wanted to have their employees stay at work and did so by making the office a desirable place to not only work but live at, and their employees start wanting to bring their lives into work.
This totalistic capture of big tech over employee lifestyles mirrors what these companies are also seeking to do at the marketplace. When a company manages not only the technological needs of their customers, but everything from entertainment, to healthcare, to home security, to shopping, logistics, and everything else, then they set themselves up to be veritable empires. That's why big tech companies are now dealing with every issue including free speech, environmentalism, worker's rights, what activities should be eligible for payment services. That's just the price of being a business that wants to be involved in all facets of human society. It includes politics. You can't be an empire and still pretend to be above it all. Both your customers and your employees are going to treat you as one.