I'll be the guy in the middle ground. As a dealer, I represent a several digital-forward brands that offer combo streamer/DAC/preamp units: T+A, Aurender, Eversolo, and now, as of this week... Grimm! (Even though I have committed to being a Grimm dealer, I don't even have my units in hand until next week, so will not make this about the MU2's performance.)
With this in mind, I have become more and more impressed with the level of performance modern integrated units are able to offer. It seems there has been significant advancement in this category over the last 2-4 years, where integrated all in one front ends or all in one integrated amplifiers have started to rise up and perform at the level of some of the better separates available on the market today. This includes the T+A SDV 3100 HV streaming DAC preamp, whose preamp stage outperforms many other $20K standalone preamps, whose DAC section beats out just about any other DAC I've placed against it, including a Berkeley Reference DAC 3 that I put into play the last few days, and a streamer at the performance level of an Aurender N20. The T+A R 2500 R all in one gets quite close to T+A's reference HV series of equipment and is now the electronics choice that Bliss Hifi will be displaying at AXPONA this year. The Aurender AP20 is yet another offering that offers similar performance with yet a different sonic flavor. I'm even amazed at what the Eversolo DMP-A10 can do for less than $4K. When I plugged it into my T+A amplifier to listen through Vivid G1 Spirits to demo for a client on Wednesday, we were not hurting at all. And these are just the options I know because I have first hand experience. I'm certain there are other brands with competitive products that may perform in the same league.
There is something to be admired about the synergy and efficiencies afforded by integrated units that are mindfully well-thought-out. Yes, there are many who want control to change one or more components, as many audio enthusiasts have the itch to do so. But for those who just want to get really far and fall in love with their music, quality integrated units offer significant advantages, primarily with synergy and simplicity.