I like that the defense against my statements are always to draw upon individual elements that don't always appear in a shadowrun game, story, or scenario.
Rather then... say... how the games are played, the stories are constructed, or anything like that.
Or rather Shadowrun without the superficial elements is still recognizable as shadowrun. It has a distinct style that shines through regardless. You don't need trolls and magic to make a shadowrun story.
I mentioned research. Sure, you can make assumptions about the coprs, but that is mostly just specialising your team against certain opposition and squatting over one part of the world. Different targets have different quirks, but that is little more than bringing along a specific key item, like stunning to hold an exec, or bringing in augs to install... A good run means datamining the target...
A strength-trained troll can, what? Roll a car? The same training on an elf will have limits... Races provide an extra layer of personnel. It shifts the ranges of abilities that can be seen in the field and creates assumptions that are reliable enough to be useful while also being open to deception. You hire someone to haul loot then you look for a troll, they are good at that, but maybe the samurai-looking thing can do the same job and is a better fit for other reasons. Maybe you try to keep the troll pinned down to stop them from bringing their strength to bear but they are actually a hacker and are throwing your tech guy out of the system and is happy to stay put. In missions, it is an extra layer of information and if that layer doesn't exist then something is missing and there is probably an important reason for that. Dragons are rare, races are not.
Additionally, races are a social thing. they form their subcultures within other communities, and their form racial communities with subcultures that parallel non-racial communities. they introduce different perspective due to their own inherent limitations and have their own background cultural issues which may or may not be an important aspect of their background. If it is all humans all the time then someone or other is a human supremacist group, or humans are somehow immune to whatever is keeping folk away, or something else weird like that which is probably somethingthat can be exploited and it really ought to be a relevant issue...
Spirits are real, magic is useful. Sure, you can ignore the existence of magic, but you can also ignore the existence of electronic security. Sometimes you get lucky and they assumed they wouldn't need it, or it broke down, or someone else defeated it for you, but just because it doesn't come up doesn't mean that it is safe to ignore its existence.
You can also play Dungeons and Dragons without magic, races, dungeons, monsters, rogues, or whatever else. You can play a mercenary campaign that takes place entirely on open battlefields. Or an aristocracy campaign where the only combat you will see is duels and anyone willing to accept is almost certainly better than you and not above using poison to rig the match or avenge a loss. Though that is kind of a massive waste of the setting and system.
Shadowrun is fantasy with cyberpunk as much as it is cyberpunk with fantasy. Now sure, you can throw away one or other half of the setting and strip out a mess of the system and still have fun with what is left over, but that doesn't mean that the elements that you removed are not an important part of the base game. Some runners don't want to mess with the corps and can have loads of fun with the little-league, or spend their time running around swamps chasing ghosts for some league of weird hermits, does that mean that you can remove the corps from the setting?
Shadowrun(S.) is generally mission-based. Invisible Inc.(I.I.) is always mission-based.
S. often features augments. I.I. is permeated with augments.
S. has overbearing and uncaring corporations that are a source of fear and opportunity. I.I. has evil corporations that are your sole and mortal enemy.
S. generally gives everyone the same toys. I.I. generally has one set of toys for the corps and a different set for the player(Let MY agents jolly mess with the bothersome system after THEY get knocked out...).
It is possible to play out the same scenario in both settings, but the Shadowrun team would be a weird group of anti-corp human-only fanatics with magic nullification and an impossible affinity for and access to cybernetics. To get to invisible Inc, you need to bend Shadowrun into some really weird shapes. They are very close, but still different animals, and just as a Shadowrun can look like and invisible inc. missions, it can also have absolutely nothing that appears in Invisible Inc. unless you want to get really general and start talking about "living creatures" and such and even then you could have spirit runners in spirit world doing a slice-of-life scenario if you just wanted to be difficult about the whole thing...