I'm no fan of ICE – a very large percentage of my friends in the US are immigrants, and I generally want my country to be a welcoming one. ICE has certainly committed unethical and probably illegal acts (probably true of most federal agencies).
But to expect that a _federal agency_ will be denied service from a private entity, especially for essentially political reasons, is lunacy. It'd attract extreme negative attention from the rest of the government, and great fear from all paying customers that an internet mob could separate them from their code at any time.
We should absolutely be lobbying hard for changes to immigration law, the restrictions placed on ICE, and justice for their wrongdoings.
But I can't see how this helps improve immigration, and it certainly seems likely to cause a lot of negative consequences for GitHub. The employees are putting their employer in a "damned if they do, damned if they don't" situation.
EDIT: Just to clarify, I love the vision of a world where executives don't take actions their workers will protest. I think that in order to get there, the protests need to be reasonable, and I think this one isn't.
EDIT DISCLAIMER: I own a small amount of MSFT stock, which was not on my mind as I wrote this. I use GitHub's free service and have no other relationship I can think of with MSFT or GitHub.
Um, think you've got this backwards. Private entities shouldn't have to take on anyone they don't want as customers (for whatever reason - do you have to justify who you do or don't want in your livingroom?), but publicly-funded institutions shouldn't be able to deny service on political grounds.
In free societies, governments should only be able to forcibly compel people not to do things (murder, threaten, steal, etc.) - see the concept of "negative rights."
The great thing about this, is that someone else will realize there is now an under-served market, and create a business to fulfill that need.
The same case can be made for hiring practices.
That is a childishly simplistic understanding of how free markets work. There is no way a retail business would be established to service the needs of 2% of the population who are wheelchair users for example, when they could easily make their stores considerably more efficient by making the aisles a little narrower.
Whether it's the kind of discrimination the store is obliged to deal with is going to come down to principles of reasonable accomodation.
So, say you had an extremely boutique store up some rickety stairs, where the way it's used is you go up the stairs and meet the chef who will take your order for a wedding cake and you can collect the cake next week.
I would expect, in that case, if the chef is willing to meet you at your home or another place with a menu of options and discuss your order, and then have it delivered next week, that would meet the bar of reasonable accomodation for someone who couldn't use the rickety stairs.
On the other hand, a large grocery store, where browsing the goods is part of the experience and is also significant to product discovery, and maybe pricing and access to better fresh ingredients and different bargains, and where the only obstacle is that the store does not replace one door type with another that a wheelchair user can enter, and the store can reasonably afford the cost, that is clearly inadequate of the store; they have no good excuse and could reasonably accomodate by changing that door.
On another hand, the same large grocery store may find it difficult to accomodate people who cannot tolerate bright illumination (that other people need, to see clearly), and large numbers of people moving around them. In that case, it is not at all obvious that the store can do much to accomodate. I would expect that if the store also provides online ordering with delivery, that it has performed reasonable accomodation for that situation.
It wouldn't be the only obstacle. Let's take wheelchair-accessible parking spots for example. We have to convince the store that sacrificing regular-sized parking spots (and the ones closest to the store, at that) in order to make room for a smaller number of larger parking spots that are reserved for 2% of their customers (and not exactly the most profitable 2%, either) is a reasonable accommodation.
Bear in mind that some of those spots we're asking them to convert might already be reserved for the store manager, some senior employees, and the employee-of-the-month as perks, rather than for customers. You will have a lot of convincing to do, and should expect significant pushback from the local chamber of commerce.