Joyent has been a subsidiary of Samsung for a few years (presumably running Samsung's internal private cloud) and I guess they are now focusing almost entirely on Samsung and their public cloud was a distraction that didn't make much money.
Samsung acquired them because of their public cloud infrastructure -- they were Joyent customers for a long time and clearly decided that buying them would be the cheapest way to continue using them. As mentioned in TFA, they are only shutting down their multi-tenant cloud and are keeping their dedicated cloud business (which is what Samsung uses).
