My prediction is that by 2030 Wordpress will be just as popular as it is today :)
Automattic isn't making any money on the open-source version that can be hosted anywhere.
My own personal site is static HTML mirrored against Cloudflare, I do definitely see the advantage when it's there :)
It seems automattic is realizing that there is value in being "the established service that does what the giants are doing but isn't the giants". Personally and I think the HN crowd would agree with me, I see the value proposition in using Tumblr, beeper, WordPress over their competitors, simply because automattic has amassed a lot of consumer trust in not running things into the ground and making interesting things out of software that seems like it shouldn't be there.
Also they hire all around the world where $100k/yr is the exception and not the norm.