Should this be considered if we already have a high quality DAC?

The answer is yes. We DO have a high quality DAC.

YOU don’t have or need one for mp3s.

As mentioned above, I wouldn't sweat the switch until you are streaming from a lossless service. Qobuz is my choice.

i denied this for a good while, but i now do believe that a better ethernet switch does matter over a bottom of barrel, cheapo, poorly designed one in preserving/enhancing sound quality of a digital feed

that said, whether one as expensive as the op is highlighting is necessary to reap the gains a better switch brings is another question altogether... just like saying better cables matter to a good sounding system, but you likely don't need to spend thousands to get better performance

Snarky post is my guess.  But I will bite:

No Ethernet Switch can make your couple of hundreds $ “DAC” sound like a SOTA DAC.

So you are looking at a 2.5k Ethernet gizmo to make the node dac sound better? Not money well spent, buy any $400 well measuring dac.