Risk means you stand to lose something so no the game mechanics do not need to become riskier.

However, for some they may want certain content to become more challenging.

SE needs to leave the MSQ alone - it needs to be available for the masses, for those who do not seek out the great challenges. It's there to guide, educate and inform the players really. To prepare them for the greater challenges.

The "end game" content for some may lack a challenge but that may be in part their fault as they have done it over and over again. Repeat something enough times and it becomes easier. However there is no simple fix for this due to the fact that the development cycle is somewhat limited and SE is acutely aware that they must not make any content too difficult or people will simply scream complaints.

SE is more aware than anyone on their players numbers and how many actually run each type of content and they allocate development time accordingly.