There are many practical political reasons for Republicans to support redistricting reform. Legislative districts are now drawn by a five-member group. The first four members are made up of the majority and minority leaders from both the House and the Senate. The fifth person chairs the group. This chair is either agreed upon by the first four members, or appointed by the Pennsylvania Supreme Court.
For the first time in decades, the Supreme Court is now controlled by elected Democrats, and it will be in 2021 when the next round of redistricting takes place. If we keep the current system and the Democrats try to take partisan advantage, there could be payback. Fair Districts PA would rather see redistricting reform that puts partisanship in the past.