I think the GOP's biggest messaging advantage is that they've managed to monopolize white Christians as a political group, and they can activate 50 million voters by casting Power Word: Abortion. The Democrats have a much more diverse coalition with much more diverse interests, can you can't activate them all through a single message.
That said, Democrats have essentially let that happen by ceding broad territories to the Republican party: religion, patriotism, and the economy. If they want to fracture some of the unified GOP support, they need to get the
Buttigiegs of the party talking about abortion, the Duckworths talking about patriotism, and Biden reminding the country that he's having to clean up the GOP's economic mistakes for the second time.