Rock Band 4 was never released on PC. In 2015, Harmonix stated that they were unsure if there would be a large enough audience for Rock Band 4 on PC. Then in 2016, it proved their concern valid when it launched a Kickstarter campaign for a PC-version that only reached half of the $1.5 million target. Harmonix has announced that Rock Band 4 DLC will cease to be released on January 25, 2018.
Harmonix released a lot music for Rock Band 4 in the past: almost 3,000 tracks, and more if game soundtracks are included. And to be clear, those songs won't be going away: Product manager Daniel Sussman said live services for Rock Band 4 will continue as usual, and “you can play the songs you own within Rock Band 4 for as long as you like.”
But Harmonix was acquired by Epic Games in November 2021 with the idea that the studio would “work with Epic to create musical journeys and gameplay for Fortnite,” and that's apparently where the focus is these days.
Sussman wrote: “The Harmonix Team has been working hard over the past two years to bring rhythm action gaming to Fortnite, bringing more to the ecosystem.” “It’s…