By far the most striking technological innovation that I've been able to experience both in film and music is Dolby Atmos. When sound is utilized properly by a director and given the room it deserves in both the production and post processes, Atmos can elevate the story telling experience of film in a way that no other format is capable of. 

Consider characters in a film reacting to a sound that cannot be seen on screen yet. In a stereo mix of the film, viewers might be able to get a general idea of the direction of that sound, but in Atmos, viewers know the precise location of that sound just as the characters do. In much the same way, when implemented skillfully, music is elevated to a fully immersive listening experience. 

Unfortunately, access to Atmos is not yet widely available, and while the best Atmos mixes offer a truly unique experience, it is sometimes seen as "another box to tick" for both musicians and film studios, making the stereo mix often more appealing when this shouldn't be the case. Consider the quality of an Atmos mix from a bedroom producer who has just started to be able to hire an Atmos mix engineer, compared to a big name musician who has absolutely no issues with the cost of producing for Atmos. Which of these two sounds better should be an obvious answer, but this is not always the case. 

Mixing engineers have been working with stereo formats for so long to a point where the format can be truly mastered. Atmos simply hasn't existed for long enough to consistently provide the same level of clarity that stereo can offer far more often than not. Perhaps what I mean then, is that I believe there are far more mediocre Atmos mixes that don't truly utilize the format, than there are mediocre stereo mixes (especially in terms of music).