Abandoning a stellar system is equivalent to giving up a piece of cosmic knowledge that humanity has mastered, and giving up a possible path of evolution.
This kind of loss is intangible yet immense.
Moreover, this was the birthplace of humankind.
Without a doubt, the physical laws of the Solar System are the most suitable for human beings.
Therefore, in accordance with biological, psychological, and various other theories, it is reasonable to say that human technological progress should be the fastest within the Solar System.
Supporting evidence can be found in the "stories" left by the ancient sage Harrison Clark.
In the timeline mentioned above, even under the dome's rule-changing suppression, the Earthlings within the Solar System managed to achieve technological progress surpassing the colonies of Barnard's Star and Proxima Centauri before the final battle.