I don't really know what to make of "republicans have had control of the Supreme Court for years." Overturning Obamacare was their number one priority during the Obama administration. The Supreme Court chose not to. The five justices who chose not to are still seated. Some control.
Scalia and Kennedy where both republican appointments and replaced with Republican appointments. So if you’re saying they have 5-4 control now they also had 5-4 control then.