>good quality DAC or audio interface (headphone jack), this is also something Apple tends to do a little better than competitors
No laptop has a decent DAC. If you want a good dac, just get something external. Don't need to spend a lot either, even a relatively cheap ~$70 product will vastly outperform anything in a laptop, desktop or phone.
To be clear, unless you are in the > $2,500 headphone space, DAC quality has a hard limit of actual hearable use.
Under that point, most external DACs are pure snake oil. If A user has $200 to spend on a pair of over-ear headphones. they should spend $9 on the DAC and $191 on the headphones.
Hell, the $9 headphone adaptor vastly outperformed a number of $100+ DACs.
The primary limitation of headphone quality onboard laptops is generally EMI, not the DAC. The Apple hardware is shockingly good on this front.
Sure, most DACs that just use off-the-shelf chips are virtually identical in terms of how they sound, until you get to the really high end, as you said.
However, in practice having a cheap external DAC is a massive improvement, even if the hardware is fairly similar.
I think a good chunk of it is just being able to give the software exclusive control over the DAC, and passing in the results bit-perfectly, bypassing any mixers in the OS or software. Many integrated setups will do dumb things like resample, convert DSD to PCM, can't handle high bit depths or rates, etc.
In my experience, it's night and day when you have it set up correctly, even with a very cheap external DAC.
I would argue this is all the high-point of Apple's desktop hardware. The same drivers that run external DACs is the same they assign to their own internal hardware. This is likely just a holdover from their background of audio production tools in the aughts.
For example, the Pro/Mac Macbook Pro supports 96Khz Audio at 32 Bits according to the same built in midi tool that you would also use to adjust the bitrates of external DACs. Sure my Onyx Artist 1 - 2 supports 24 bit at 192Khz...but the external headphone jack in the latest Macs also adds a fun bonus: A built in Amp for headphones over 300 Ohms. It's a weird add, but a wonderful one. (I do dislike that it is just a resistance detector that enables it though, my Planar HifiMan headphones are just under the cut so I have to drive them with an AMP for better sound.)
Obviously, this all goes out the Window on iOS of course.
I had a (in hindsight) hilarious issue with this at one point.
I have a big GPU. Big GPU makes noise. That noise goes through the PCIe connector and into the motherboard. It then made it to the ethernet port. It went through my ethernet port to my ethernet switch, which then made it to the Raspberry Pi I was using for streaming, which went into my DAC, AMP and finally speakers.
It was because I was using shielded twisted pair, which connects the ground plane.
No laptop has a decent DAC. If you want a good dac, just get something external. Don't need to spend a lot either, even a relatively cheap ~$70 product will vastly outperform anything in a laptop, desktop or phone.