Streamer v DAC - which is more important?

As a broad generalization, I think the DAC is more important, however it all depends on a lot of factors. For example, does your streamer output/passthrough the file type you're wanting to listen to? If you want MQA or maybe some other file type, you need a streamer that can pass that info to the DAC. You mentioned having the CXN to compare. I don't remember the details, but I know the CXN really isn't intended to be a streamer going out to an external DAC. I believe it only exports CD bit rates regardless of the source. So it might be downscaling some file types. That's an example where you're streamer might matter at least as much as your DAC. 

Another factor would be if you find your DAC sounds best via a certain input. Sometimes that's USB, sometimes IS2, maybe something else. Well if you DAC sounds best via IS2, you need a streamer that has an IS2 output. 

So like most things in audio... it depends. 

That very question was put to the test recently during a get together at a acquaintance home where he quickly demonstrated playback comparisons through a home baked Jcat ? server / streamer and a very expensive net work switch along with a selection of wires , modem , service and a hideously expensive dac to the rest of his system. We listened to a verity of known well recorded music.
He then bypassed his server streamer and Uber up stream components switch and all to a basic components and wire and kept his 30 grand dac in place , playback wasn’t nearly as enjoyable.
Actually there was a shocking difference.

I certainly do not own anything that remotely comes close to this fellows system however I know what actual music being played should sound like and this illusion was a tiny bit closer to the real thing with everything in place including a 5 grand network switch thrown in the mix.

I don’t stream music yet my library of music is ripped to a dedicated server and I have a fairly decent dac however today good performing dacs are a dime a dozen ,
 I’ve always considered the source especially the quality of recordings to be all important and still think so , actually it’s all important.

I’ve used the Bluesound Vault2, a Bryston BDP3, and a Melco N100 as 3 different streamers into the same DAC, a Bryston DAC3.  They all sound different, with the Melco and the Bryston besting the Bluesound.  So I think the streamer matters, but the DAC is where I would put most of the budget

Mahler I would agree to a certain extent today with fast moving technology I chose a 1 bit FPGA dac with separate power supplies all are upgradable with firmware updates , I feel good about that and it performs very well.

Streaming is a new frontier for me and I’m reluctant to dive in for now , I have access to a huge collection of CDs I borrow to rip and so far I’m content with that .
My server was a Black Friday special from a actual audio store and though it had a retail price in the thousands it was heavily discounted being a store and audio show demo model.
ive had another borrowed server to compare and noticed a marked difference in performance and someday soon I’ll sell off my original  purchase.
Though for now I’ll enjoy what I have and see what unfolds in the very near future.

Slightly off topic, but have you ever thought about using a different app for your CXN?

I have used Bubble UPnP for Android and I think it's light years better than the stock Cambridge Audio app.