You are completely right....
Telemann worked after the era where music was merely Church order or Prince order, but now middle class and bourgeois commands and demand was enormous and the musicians amateurs numbers too, and Telemann was a self taught musician and did not come from a musical dynasty , he taught more to amateurs musicians not like Bach who was busy with his multiples children...He then used the amateurs playing musicians and apprentice composers around him like Bach use his children ... Half of the work of Telemann is lost... And of the remaing half, half had never been performed...
i like your sentence :
It may not storm the gates of heaven like J.S. Bach, but it paves the streets leading to those gates, if you will accept that mixed metaphor