The statement appeared to be a callback to a monologue Hayes gave back in July in which he accused Trump of "failing on all fronts" in his handling of the pandemic.
"If you take the steps that Donald Trump is taking, not just refusing to combat the virus, but actively taking steps that will make people sick, then you are objectively pro-virus," Hayes told his viewers.
The tweet "objectively" sparked backlash on social media.
"The state of American media today," Quincy Institute fellow Max Abrahms said.
"Chris Hayes is objectively a lunatic," filmmaker Robby Starbuck reacted.
"Biden and your network are pro it as they hope it sinks Trump in November," political commentator Yossi Gestetner told the "All In" host.
"Chris Hayes sees his progressive colleagues in the media saying really stupid things and getting coverage. So, he decided to try to compete again," radio host Jason Rantz said.
"This tweet perfectly captures the state of the Orange Man Bad media in 2020," journalist Jordan Schachtel declared.