[Richard Prowse]

"Moderation is a fatal thing, nothing succeeds like excess"
Flint, take note of your own signature!
You say:
"And yet it was depressing because, even though I can “hear” the music in my head, and visualize myself doing it, I know that I simply started too late to ever do what he’s doing. I can certainly relish in the performance of others, but I admit that I wish I were able to carry on such a lyrical conversation with my own instrument."
Your public profile says that you are under 40. You have plenty of time to improve your playing beyond your wildest dreams!
How?
1) Regular practice... get to really know your fingerboard through regular scale and arpeggio practice.
2) You must work on an etude (or 2 or 3). This could be a piece of music like the Prelude from Bach's first cello suite (in cello range). An etude must force you out of your comfort zone.
3) You must start building a repertoire of things that you can play.
4) You must know that, when Mr Meyer puts bow to string, he faces the same physical problems that you face. Imagine if you could get to be half as good as him, possibly even 5/8 as good. If your body generally works okay this is possible. If you get to be 1/2 as good as Mr Meyer (and you aren't prepared to stop at this point) you are certainly on the way!
5) No one does F. Buchanan as well as F. Buchanan. Apply this simple principle to your playing. Give your playing its own voice.
6) Listen carefully. Listen to all the sounds around you.
7) Make sure that your bass is set up well.
8) Study how that bow works and make it an extension of your arm.

Aim for the sky and you may get to the top of the tree.

You are under 40, I am 54. I play much better now than I did at your age... I know this for a fact. I am seldom happy with my playing but, when I stand back, I can see that I've improved immensly (especially in the last 3 years!). The one lesson that I've learnt well in life is that thoughtful regular practice (backed up by clear goals) makes you get better.
People may laugh and say I'll never be able to match Edgar or Gary. This may be true, as it is hard to compete against such bounds of natural talent.
As far as I know, you only get one crack at this life. You've only got yourself to work with, so you might as well 'go for it'!
If I make it to 75, and there's a good chance the old body won't last that long, watch out Edgar!