Just 9.85 million US viewers tuned in to the ceremony, a drop of 58% from the previous low of 23.6 million in 2020.
Interest in the event was dealt a double blow by the lack of blockbuster contenders, and audience fatigue with drab Covid-era award ceremonies.
And despite historic wins for Anthony Hopkins, Chloé Zhao and Daniel Kaluuya, reviews were overwhelmingly negative.
TV Line deemed the event "a painfully earnest snoozefest", while IndieWire called it an "insiders' awards show [that] collapsed under its own weight".
The Arts Desk said it was "dispiriting throughout" and asked why winners were allowed "to yammer on incessantly".
Even Variety's more upbeat review took issue with its "insistence on upending its own order for the sake of it".
In a pandemic-necessitated break with tradition, this year's Oscars were moved from their usual home at Hollywood's Dolby Theater to Los Angeles's Union Station.
The Hollywood Reporter's Scott Feinberg felt it was a fitting location for the ceremony given "it was, in some ways, a trainwreck".
"Far too many decisions were badly miscalculated," he continued, lamenting the absence of a host, live music performances and the usual array of film clips.
"The ratings will be out tomorrow," he concluded. "My guess is they will not look pretty."
Other innovations this year included having the best actor and actress awards announced last, instead of best picture as is customary.
That resulted in an awkward end to the ceremony - where an absent Sir Anthony Hopkins was named best actor for The Father, edging out the presumed favourite, the late Chadwick Boseman.
"Like most of the world, Sir Anthony was apparently not watching the Academy Awards," said Entertainment Weekly's critic of the show's "dull thud" of an ending.
IndieWire's Ben Travers, meanwhile, said it had resulted in a finale where "everyone [was] reminded that a black man rarely wins best actor".
Only four black performers have ever won the best actor Oscar, and the last to do so was Forest Whitaker in 2006.