Sorkin has noted that when scripting The West Wing, he never referenced any recent President (I think before Ford, but it could have been further back). The sound logic was that once the point of reference was too close, the viewer subconsciously made a mental calculation of where the fictitious cabinet fell on time, and it felt less grounded as a result.
With Being the Ricardos, I think there’s a parallel. Anyone who actively watched I Love Lucy has such a firm representation of the cast in their minds, that our brains are effortlessly picking apart anything that doesn’t conform to those expectations, and it unfortunately makes it difficult to stay in the moment when watching this film.
Let me be clear; the acting was fantastic. The script was fantastic, and the directing was fantastic. If this had been a play and I was anywhere behind the 6th row, or if I’d only casually seen clips of Lucy’s show/life throughout the years, I’m confident things would have been just blurry enough that may mind wouldn’t be doing mental gymnastics to reconcile the movie with reality, but it was hard to do that in high definition, watching the movie in the comfort of the same home I watched the show it was based on in.
All that said, if you can divorce your mind from the need to reconcile the actors’ physicality and cadence from those of the actual Ricardo’s, then you’ll enjoy an exceptionally well written, acted, and directed story.