I used to think the same until I listened to the “nostalgia” channel on a certain Jewish music portal. Even tracks I remember from when I first became frum, which is about when recording technology started to advance rapidly, really don’t have the sound of today’s music.
However, indeed, it does make it easier for mediocre singers to force out a disk, and for better singers to force out mediocre disks just to stay in the limelight. With the radio stations and samplers, though, there is no reason to buy a substandard release or an album that is not for you. In the end, the substandard stuff falls to the clearance rack anyway.