Stellaris has undergone a significant amount of power creep over the years, and the speed at which we're able to burn through the entire technology tree is much higher than is healthy for the game. Due to the large number of stacking research speed modifiers, repeatable technologies are reached far too early in the game. Another power creep issue mentioned by many players, it's also become trivial to stack large numbers of ship build cost and ship upkeep reduction modifiers.
The Holiday Open Beta will be a feature branch that contains the following changes, which may or may not go into 3.11 (or 3.12, or any release at all for that matter). Similar to how we handled Industrial Districts several years ago, we're intentionally keeping these separated from core 3.11 development, isolating this in a parallel track.