R² is 0.38: a reasonably reliable fit; the betas and the split below are worth reading at face value.
Note: the net move here (+54.2pp) is small relative to the systematic and idiosyncratic swings underneath it; they're largely offsetting each other, which is why the idiosyncratic share below exceeds 100% (it's dividing by a small net, not an error). Read the pp values themselves as the meaningful numbers here, not the ratio.
Of GOOGL's +54.2pp move over this window, +55.2pp (102% of the total magnitude) is idiosyncratic, not explained by riding market, sector, or rate moves. The rest (-1.0pp) came from systematic exposure: market +27.7pp, sector -28.6pp, rate -0.0pp.