I have seen a video of Reach on Youtube in 4K for the PC. Its is coming to the MCC for the PC after all.
This means more Halo action on the PC and all those custom maps will make the Halo universe the place to be on the PC.
if the release price is reasonable I can expect Steam sales of several million copies in the first couple of weeks
microsoft games has been publishing a lot of games on Steam and besides Halo many of the RTS games are updated for modern systems
With so many other games out there any new Halo release will have to be over the top AAA in quality
Even then competition with other AAA action games is fierce