If you connect to make.powerapps.com / emea.flow.microsoft.com you will be routed to the default Environment. If you work in a large organization you likely have dedicated Environment for teams, entities, projects etc. and do not want users to create resources in the default Environment.
It would be nice that each user gets automatically connected to a dedicated Environment if the user has access to 1 or more dedicated Power Platform Environments apart from the default Environment. Here's the suggestion:
We secure each Environment with a Security Group, only the Default Environment is not secured with any group (as it’s not possible)
If a user is part of a Security Group which secures an Environment, this Environment should be set as default (While loggin into make.powerapps.com / emea.flow.microsoft.com the users security group memberships are fetched => if one of these groups also secures a Power Platform Environment => forward to this Environment)
If a user is part of multiple Security Groups which secure multiple Environments, just take the first one that is found (it’s still better than to be routed to the default Environment)