My streaming rig (streamer and DAC and interconnect) is modest (by this channel's standards) at ~$6k. My analog (tt/pre/arms/cartridges) is slight higher.
On my system, analog sounds significantly better for most recordings (old jazz and R&B). Fwiw, my cd player is also $6k and doesn't sound as good either.
That said, as several others have noted streaming kills analog it in convenience.
So for practical reasons I would turn the question on its head. Assuming, I am still talking about music created wit analog mastering, how much will I need to spend upgrading the digital side to not be able to tell the difference.