target the largest market segment to gain the most conversions.

Windows market share is bigger in desktop only. In fact, is kinda sad that still there are serious institutions using Windows for non-desktop stuff. I hope this incident changes it.

the real difference is you need a few decades of linux experience to fix anything in a timely manner.

[ citation needed ] Probably you are meaning desktop again. Although troubleshooting Windows is not easy task neither, there are way more desktop users familiar with it.

The real thing is

• 1. There is no single "linux" OS. There are lots of different OSes based on Linux kernel. And they are for servers, desktop, embedded systems, smartphones, etc.
• 2. More important. Security is a process, not a product from a vendor. The root cause of this incident is that some institutions are seeing that you just buy "security", install it, and call it a day. No important stuff should auto-update. And no institution should auto-update lots of important stuff at the same time.

So, Linux is not really more secure. But is built in a culture where security is taken more seriously.