I’d like to see some statistics backing up the supposed consensus.
I suspect it’s directly down party lines.
While I’m no Reagan defender, quite a lot of time has passed since then and both parties have changed a lot. Republicans tend to praise Reagan as an article of faith, but frankly he’d be viewed as a fringe liberal in today’s Republican party. On some issues he’d be fairly liberal for a Democrat these days too. Top marginal tax rate of 50%? Pffft! Go back to your Bernie rally, Ron! Evil Empire? Fake news!
So if you ask “What do you think of Reagan?” I agree the answer will be split down party lines, but if you ask “What do you think of these specific policies?” the answer may also be split down party lines, in the opposite direction!