I know it bothers some people, but I personally have no problem with it. I tend to go with Carl Rosenthal’s prescription here:
If you read between the lines in his and other similar prescriptions, the rule is basically a 1-2-1 relationship is fine as it will be instantly recognized by the performer. If the “1” is overly difficult then maybe I’d break the 2 if needed for clarity in a meter like 12/8, but generally I don’t.
The obvious complication with this is that some rhythms that are allowed in 2/4 are then not allowed in 4/4 as they are no longer a 1-2-1 relationship. People tend to think of rules about eighths, quarters, and beats and miss that key relationship element that professional readers instantly recognize.
While the rhythm in the 3rd bar above is clear and comes up in the literature all the time, it’s not usable in the the 5th bar with the exact same note values as the eye loses the beat placement due to the fact it’s no longer a 1-2-1 relationship. The 6th bar must be used instead of the 5th, even though the 3rd is fine in 2/4. Overly notated bars like the 2nd slow the sightreader down as there’s more unnecessary visual elements to process.
I know over on the MET FB group people are neurotic about showing all the beats (2-level parsing rule, etc.), but it’s not really helpful for the reader when a common 1-2-1 pattern is easily recognized. Bar 3 above is perfectly readable even though 2 levels up from 16ths would mean to show the quarter beats. Professionals recognize rhythmic patterns in chunks of information, and don’t read strictly from left to right. We don’t place a half note on the & of 2 in 4/4, because it will break the recognized patterns in the bar, even though it might not matter to a beginner who is counting literally from left to right. As 1-2-1 is an easily recognized pattern as well, breaking it to overcomplicate it slows a professional reader down.