Will the Topping E30 II support Tidal's FLAC streams?

I think the most important aspect of a DAC is how it sounds. The overall sound quality is of the highest importance. Then it’s ok to verify it supports typical formats.

If I was in the market again, get the best sound quality possible… making sure it supports Qobuz. Qobuz sounds better by a small amount than the rest and has over half a million more high resolution albums, making it the only choice for folks interested in high quality sound. .

If you want etched details. sterile and boring sound, Topping is the way to go. I know they have mastered the 'measurements' game (looks so pretty and perfect on graphs) and are favored heavily by that 'other' site. I tried their DAC a couple of years ago and couldn't get rid of it fast enough. 

I don't know what your budget is, but if you want good sound consider Denafrips Aries or Musician R2R dacs.

Who cares if it decodes Tidal’s myriad of confusing formats?  Just switch to Qobuz where everything just works and you have tons of hi-res recordings as well.  Put Tidal in your rear-view mirror and say good riddance.  

 FLAC can be encoded up to 32bit PMC so when they say it does PMC it does FLAC.  double check with others but that's my understanding. 

A streamer has to care about the format / service that it connects to. 

A DAC only cares about the sample rate, frequency and encoding (PCM or DSD).

Most streamers let you configure the maximum bits and sample rate.

Sample rate is number of points/second.  Say 44.1 kHz = 44,100 samples per second. Bit depth is how much resolution each of those points can be.

CDs were 44.1kHz at 16 bits /channel..  Common Hi-Rez is 96kHz or 192 kHz/24 bits. 32 Bits are also possible.