MCC's existing issues are not preventing new people from playing the games. If anyone such as myself really wants to play any of those Halo games they, like me, will go in and play them regardless of any matchmaking limitations. I know what I'm getting. However what does keep me from playing the game is it not having reach which is my favorite halo aside from H2. For too long reach haters have been the loudest people in all discussions involving this game. "It's the master chief collection not halo collection" "reach is a bad game." Meanwhile ODST is on MCC even though it clearly has no master chief in it, and reach still boasts a healthy-ish population 8 years down the road and still has people jumping onto the 360 version to play 30 fps on laggy p2p based matches online just because they enjoy the game that much.
A simple port to xbox one is all we need not a remaster. Matchmaking on dedicated servers with choose-able p2p hosts in custom games, and a bump up in fps would be VERY welcome additions to reach and would be the end goal here as to why Reach should be on MCC. Would it split the population? Yeah so does low fps and lag all the time, so does having the game be on a deprecated console from 10 years ago. People still playing 360 need an incentive to buy an xbox one. Realizing their favorite game is essentially moving on to a newer console is as much of a wake up call as those people will ever get, its 2018. Also, let's not pretend existing MCC players won't play reach if it launches. They will also play that game and help keep the population up. Reach will live, and MCC will live. Bringing Reach into MCC would be one of the smartest moves they'll have made in a couple years.