For what it's worth, DMR-MARC Worldwide is rarely used by anyone here in the U.S. with the exception of the Saturday morning net. Most U.S. traffic is on North America, Regional Talkgroups, or Statewide Talkgroups... There's also DCI 1 & 2 and COMM 1 & 2 from the DCI group and then there's the Bridge Talkgroup.
Check your c-Bridges reports, there's far more traffic, repeaters, users, and projects going on with MOTOTRBO, Hytera, etc. than D-Star and NXDN combined.
That's not to say one format or the other is better; it's just saying that the growth goes to speak volumes about how groups should interact with one another towards a common goal. You need structure and organization, not a bunch of hap-hazarded networking and installing.