... even the latest ColorFly C10 abandoned their traditional 1/4" output port
Can you name at least one mainstream popular DAP in the last 1+ year with 1/4" output? I don't count "boutique" LP5 Gold since that was luxury&precision reminiscence from colorfly days
Just think about it, who is driving headphone output connector demand? Headphones. When everybody is switching to low impedance portable efficient ones with 3.5mm connectors and manufacturers trying to keep their daps slim - 1/4" HO is no longer a popular choice for portable daps. Just a reality. For big hard to drive inefficient cans, people use external desktop amps that come with 1/4" or XLR, etc. For portable use with efficient headphones - 3.5mm ports. Or an external portable amp with variety of ports and built in battery to drive demanding cans without draining DAP's battery.
And dual stacked uSD card readers, like in DX80, are also in demand. Amazon has 200GB uSD for $59 (on back order, though). Soon, I will have a hard time finding SD cards for my LPG and will end up using uSD with an adapter lol!!!