This "modern" practice of liberal use of sound effects, music and other background audio behind the narrative or dialogue poses two major problems.
Firstly, many viewers clearly find it annoying and distracting. As such, the taste and needs of the audience seem to be at odds with the beliefs and fads of an industry that likes to think of itself as cool and trendy and in continuous search of "creative" ideas to make content more "attractive".
The second problem is more fundamental, as it is not a matter of conflicting taste and desires, but one of access and usability. That is to say that the practice of plentiful and often intrusive background audio creates a real access barrier for millions of citizens with less than optimal hearing. A very common corollary of (even mild) hearing loss is that people experience difficulty in discerning speech from background. Even minor hearing loss leads to a noticeable reduction in audibility or intelligibility of the dialogue, well before the hearing loss would be clinically identified by traditional audiometric measures.
Hearing for high-pitched sounds is usually worse than for low-pitched sounds. This means that low-pitched sounds like traffic, fans and air conditioning or rumbling background effects and music are more likely to cover up the sounds of speech.
Also, for a person with hearing loss, the cochlea often no longer properly separates out the different components of sound. This means that speech and music may appear distorted, blurred or muffled, even when they are amplified.
Turning up the volume will not necessarily improve intelligibility and may even exacerbate the problem. The louder the background noise, the stronger intelligibility is affected.
While artistic arguments could be labelled a matter of taste only (even if it seems unhelpful to force this fashion upon an unwilling public), where it becomes an access barrier, clearly artistic licence ought to give way to accessibility.