Isn't Tralfagar considered a good polling company?
They predicted a red wave and had Oz beating Fetterman in Pennsylvania in 2022, they showed a much closer race for governor in Pennsylvania that year,, and their polling showed Tim Michael’s beating Tony Evers for the governorship here in Wisconsin also
They also showed Dixon possibly eeking out a win over Gretchen Whitmer in Michigan that year.
They may or may not be a good polling company. But they did overestimate Republican enthusiasm in 2022
We saw this same thing with the polls with Romney versus Obama in 2012. They over estimated Republican enthusiasm and underestimated Democrat enthusiasm
Romney ran a good campaign and he handled himself very well in the debates with Obama. But Obama was able to get out his very enthusiastic base and even outvote independent voters
This is the same model that the Democrats are following with Harris.