On the points:
A: This may be less necessary than I believe admittedly. I've only worked at companies with 100+ people before, all who gave similar hardware. The advantages were in the ability to swap computers. If your computer dies, you get a spare immediately (you can even swap the HD!) as repairs occur. If someone leaves, the computer can be given to the next hire (or an intern).
B: Our dependencies are all open source. The full system though (needed for testing) uses kernel modules which don't have a (fully working) mac port.
C: That's good to know. (hopefully easy on OS X -- no one currently in the company uses it).
Finally, again in the companies I worked, it was pretty much expected that company development stayed on company equipment, mostly for security issues. Is it pretty common in companies with < 20 people for devs to bring their own machines?
With A: Standardization is good but it probably takes at most a day to setup a new computer. It takes weeks to learn and master a new environment though. Productivity is probably paramount in a small company more than standardization.
B: Ah, but if your dev could get it working on a mac, would it be ok? If not why? How about BSD, or some other linux distro different from your intended setup?
C: As someone else mentioned elsewhere, enforcing restrictions is easier said than done. The key question to a dev is why? In some ways that just discourages devs away from working on the project as much as they like.
The key point here is that in a small <20 company, you want to attract the best talent that's out there. Someone who's at the top of their game. Most likely they will have their own machine with their own setup. A % of them will likely stick to their own setup instead of using two computers.
You may employ contractors too. That makes it even more likely they prefer their own machine.
Being offered a choice, i.e. You can use your own computer, and here are some things you need to do too (encryption, etc) or here's a brand new one all setup is infinitely better than You must use this only
On the points: A: This may be less necessary than I believe admittedly. I've only worked at companies with 100+ people before, all who gave similar hardware. The advantages were in the ability to swap computers. If your computer dies, you get a spare immediately (you can even swap the HD!) as repairs occur. If someone leaves, the computer can be given to the next hire (or an intern). B: Our dependencies are all open source. The full system though (needed for testing) uses kernel modules which don't have a (fully working) mac port. C: That's good to know. (hopefully easy on OS X -- no one currently in the company uses it).
Finally, again in the companies I worked, it was pretty much expected that company development stayed on company equipment, mostly for security issues. Is it pretty common in companies with < 20 people for devs to bring their own machines?