Streamer v DAC - which is more important?

My two cents? The DAC is more important as that is where the data is converted into an analog signal. It's the spot where jitter, distortion, frequency non-linearity and noise can end up in the sound we hear.  Until then, the streamer and all of the other devices upstream are simply handling data packets. Now, that's not to say that the streamer isn't important. RFI control can be done poorly, or well, for example. And, the streamer and its associated programming is where we interface to select music, build playlists, etc., so a poor design here can certainly leave us with negative thoughts that may affect our perception.

I vary endpoints and sources. Having a high quality stand alone DAC is worth every penny paid. Because so many manufacturers are adding a DAC to whatever they make I expect to find one on the next toaster I buy. The side effect is a perceived diminishing importance of the DAC. The fashion on the marketing end is streaming transport DAC combinations and since money follows fashion, I expect a lot of marketing hype telling me why I need such and such. The power supply, processing architecture and analogue stage of a stand alone DAC has a massive impact on the sound. Night and Day differences between manufacturers using the same chip. Paul from PS Audio has a great video explaining this question,why specs are misleading and why the output stage is so important.  
https://youtu.be/McoA82-fi9s

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