That’s probably just the GM’s own personal opinion.
CCP originally coded the game with various options available so that players could become positive with all Empire Factions. CCP just didn’t make every single one of those options known and left it to the players to find out for themselves.
When I first started playing in mid 2008, the general consensus was that after training up Diplomacy level 5, players had to either alternate running missions and storyline offers for each set of allied Factions or make a choice as to which set of allied Factions to side with, basically cutting off access to that half of Empire space.
At that time there were only 3 Career Agents (3 sets = 9 per Faction) instead of the 5 Career Agents (3 sets = 15 per Faction) currently available. There were also 60 (15 per Faction) different single mission Event Agents known as ‘Tutorial’ Agents who gave a small Faction standing increase. There’s also another group of Event Agents for each main Faction called the Circle Agents along with Data Center Agents and Cosmos Agents.
The issue at that time was that most of this content wasn’t well known, it wasn’t generally publicized nor was it all documented and grouped together.
The 60 ‘Tutorial’ Agents were not well known and the Circle Agents were pretty much unheard of. Back then the Data Center Agents cost a fortune to start due to the Level 1 Agents requiring 20 Pirate Tags instead of the current requirement of 3 Tags. The Cosmos Agents themselves take a lot of time to complete and require Faction standing to access their content.
Around mid 2009 CCP added the Epic Arcs to help players gain Faction standing more quickly. Towards the end of 2009, I spent 3 months doing research for all Event Agents that gave Faction standing increase, gathered all that info, documented it and released the ‘Faction Standing Repair Plan’ to the community at the start of 2010. Eventually due to constant rework of the NPE (New Player Experience), CCP removed the 60 ‘Tutorial’ Agents.
CCP also changed the standing requirements for Agents making level 1 Agents available to all despite having negative Faction standing.
So yeah, I don’t think CCP actually wants to stop players from having positive standings with all Empire Factions. However it wouldn’t surprise me to know they’re making it a bit more tougher for players to maintain positive standings since the info on how to do it is more known now than it was before.