I'll take a bootleg over a live recording, and sometimes over a poor studio recording. I'd be curious to know more about the forces behind modern studio recordings, which are typically dry as a bone both musically and dramatically. Part of this is probably just how producers want albums to sound now, possibly with consideration of how people are actually listening to music.
I used to have almost all of Sondheim's OBC recordings on vinyl record, and when played on my stereo the effect was thrilling because the producer, Thomas Z Shepard, is incredibly good at creating space for the music. Compare the finale of Someone in a Tree from the original Broadway album and the 2005 revival album. In the former, it's like this wonderful, textured wave of sound, which is partially thanks to the bigger orchestration but also the space and reverberation actually given to the voices. In the revival album, it's almost the exact opposite, every voice in a crisp box, never really merging even when they're all put together, which has the weird effect of making it feel both less intimate and less grand.
There's also the way that modern vocal performances, particularly in choral moments, lean towards a scrubbed glee club style, which contributes to a lack of blending. As Ravenclaw mentioned, the Oklahoma! revival album sounded very, very clean. In the theatre, the big choral burst at the beginning was exactly that, a burst, a communal voice, but on the album it sounds more like a timid barbershop quartet. It's a very frustrating trend.