When Obama was trying to pass the stimulus bill in 2009 the magic words he used to force Boehner and McConnell to act were: "You can't just listen to Rush Limbaugh and get things done."
Interviewers were saying his name on air to Republican politicians trying to look intelligent and honest as they rationalized their obstruction and it was like they had been sprayed by a skunk.
Trump and Limbaugh are well coordinated and have been since at least 2014. That includes calling COVID a hoax, going through various stages of downplaying severity (like the flu, common cold), politicizing mask-wearing, and calling for herd immunity (I wonder if Limbaugh transcripts have him calling for ‘herd mentality’).
A lot of Republicans know talk radio is a huge part of why we are in this disaster. If Biden wants to connect with those Republicans and ‘independents’ and even Democrats who might be having second thoughts about their incredibly stupid last vote and are starting to feel like dumbshit Putin tools, Biden can give them someone to blame. Give Limbaugh and the other Republican talk radio liars the ‘credit’ they deserve for doing Putin’s work (as Dr Fiona Hill suggested).
Biden doesn’t have to fact check Trump or waste time responding with details. Any lie or stupidity or personal attack coming out of Trump’s blowhole has very likely already been preceded by months and years of talk radio repetition (‘deep state’, immigration, voter fraud, Hunter Biden, etc) that could easily have started in Russian think tanks.
All Joe has to say is, “Well, that’s what Limbaugh says...”