When will there be decent classical music recordings?

"I don't think composers necessarily wrote for concerts....".  

Could be I'm taking that out of context and, as a result, misunderstanding, but in the days before mass media and electronics, how else would a composer have their work heard other than by live performance, i.e., in a concert?

What I am saying is that in those days the composer wrote the music.... and the only outlet was a concert. Doesn't mean he wrote to accommodate concert precepts
In a similar way, Tchaikowski wrote his violin concerto without understanding the violin - hence it is so difficult
They write the music - and then get it presented in whatever way is infradig at the time

I disagree with your assumption that classical composers would ' would have been excited if they could have presented their music in effectively another dimension', given that their music was either presented in a concert hall or salon(for small ensembles). To me the homogenizing of various instruments is what makes a classical piece worth listening to.
-Just listen to late Mozart when his use of winds and horns really shine. 
If you record each instrument closely you lose the effect the composer was trying to make.

Am I incorrect in assuming you (tatyana69) are speaking of orchestras, music written for them, and performed in a large concert hall? Well, there is also "Classical" music written for smaller ensembles meant to be performed in smaller venues. "Classical" is used as a category for all "composer-written" music, but there are, as you may know, different periods within that form. During the Baroque period (1600-1750) there was a lot of music written for solo instruments (harpsichord, cello, violin) and small ensembles. And there are many incredible recordings of this music, where the intimate details of each instrument can be clearly heard from a close perspective, not dissimilar from those in "Pop" recordings. I have some harpsichord recordings which put the instrument right in front of me in my room. Or, even better, me right in front of the instrument in the room in which the recording was made. Look for Trevor Pinnock performing music for harpsichord on the British CRD label (on LP) for some electrifying music, recordings, and reproductions in your music room!

There are many sources of great recordings.
Here is a fast sampler:
http://www.linnrecords.com
XRCD ...http://www.elusivedisc.com/Home-Of-XRCD/products/859/