Is it the year of the Linux desktop?!?!
As a developer who does server-side stuff, a mac was an obvious easy choice for a long time -- a tradition that has been widespread going at least as far back as dhh's intro to rails development using textmate [1].
What does that open source crowd want now? They want to build OCI/docker containers and deploy them to kubernetes clusters. You can do that on mac, but these containers need to run on a linux kernel, so the setup winds up as containers on a VM on the host OS.
If your dev machine is linux, you can remove the VM layer in between and the setup is simpler and more efficient. I think that might push a lot of developers from mac to linux. I just got a new dev machine recently and it's a linux laptop.