We, alone on earth, can rebel against the tyranny of the selfish replicators '.
Most reputable "replicators" do provide some UV protection, and some even provide an inexpensive and relatively effective polarization.
Battles with the Replicators and the Wraith continued to plague the Expeditionary Force through the series conclusion, when the Ancient City was relocated to Earth.
Based on the creatures intiially introduced during SG-1's second season, these human form Replicators were actually created by the Ancients thousands of years before to destroy the Wraith, but something went wrong.
The replicators organized and evolved into their human forms, including political and cultural differences of opinion.