https://wccftech.com/gears-5-map-builder-functionality-removed-as-the-studio-focuses-on-new-projects/

Earlier this week, The Coalition revealed that the Gears 5 Map Builder functionality would be removed from the game as the team is now focusing exclusively on new projects. Sadly, this means none of the custom maps made so far for the cooperative mode Escape will be available going forward.

At least The Coalition is unlocking all related Gears 5 achievements for all players. Additionally, if you've completed “I Made it All By Myself” you'll receive an exclusive banner, and if you've completed “Homegrown Hive” you'll receive 10k Coins in-game.