Those are all fine records - nice bits of playing (disco never wanted for musicianship)
But in all honesty I hear nothing that matches "You Me Me Feel Mighty Real" or "Lost In Music" or "Rock With You"
So I stand by my opinion (which is not something I've plucked out of my arse - I've listened to a lot of this stuff, compilations of disco deep cuts, got friends fanatically into this area who over the years have done things like make me a mix of records played at The Saint during its heyday that they've paid $100 for each. I was buying disco and post-disco stuff in the early Eighties). It's empirically grounded.
But to push it a little nearer a thesis rather than a mere opinion....
Let's think about the premises on which disco is based, what would constitute its metric of excellence
Good beat / good groove
Strong vocal performance
Great melody
Musicianship / professionalism
Cool shiny production
Now those happen to be exactly the same premises on which successful pop music is based - a beat that you can dance to, a tune you can sing along to it, a certain conventional idea of vocal power, bright slick production, well played etc
The only difference is that pop would also value a measure of personality, whereas in disco, a certain characterlessness is not considered a deficit. There is an anonymity and a functionality. Most of the people dancing to these underground disco tunes wouldn't necessarily have any idea what the singer or performers looked like, unless they did a PA in a club. There might also be in pop a slightly increased emphasis on having more interesting or unusual lyrics, but then again a lot of pop is lyrically inane. Lyrics are very low priority in disco, which is not to say that there aren't great disco lyrics - the Chic / Sister Sledge obviously, and August Darnell, etc
And yes the disco aesthetic has all the stuff to do with extended versions and long breakdowns - 12 inch orientation.
Nonetheless the greater part of the essence of what makes a disco song appealing and successful on its own terms are remarkably close to the reasons why it might crossover and become a pop hit.
That doesn't work with every kind of underground music, obviously.
The premises on which heavy metal is based don't translate into pop terms. The more poppified a metal tune is, the less heavy and the less metallic it is, according to the genre's own internal metric.
So for instance when a really big heavy metal group like Iron Maiden went in at UK Number 1, by dint of having such a huge fanbase it could bypass the lack of radio play, that tune stuck out like a sore thumb in the charts. Whereas a club track crossing over just sounded like more pop music.
Same with ardkore
Quite a few of the best old skool rave tunes were actually Top 20 hits – Prodigy, Urban Shakedown, SL2, etc.
But the properties and principles that define ardkore are not the same as pop music
There is an area of overlap with pop - a degree of anthemic-ness and a certain fizzy euphoria within hardcore (especially Production House and the happier side of hardcore) that works on pop terms. But there are the druggy sounds and stabs and frenzied breakbeats and sub-bass - core elements of the genre that are not only a bit much for pop, but are not properly audible on a transistor radio or a standard TV with its poor bass response etc.