Are you saying per the ACS, every student pilot in the United States needs to operate in Class B airspace?
They need to be capable of doing so, yes.
Put another way: Would you hire an instructor who didn't teach you how? Would an instructor who didn't be doing you any favors?
Besides, as Doc Bruce says, "Don't accept minimum standards." They're minimums for a reason. Everyone should strive to *beat* the minimum standard. Not just meet it.
Obviously, if you can exceed the standard, a checkride is almost a non-event.
Hold altitude within 200'? How about 100'? How about 50'? How about "Don't let the needle move."?
Land within 200'? How about land within 100' and hitting 200' on the ride will be a cakewalk?
But in this case, "operate in" is the *minimum* standard.
Everyone has stuff they're not great at. Instructor will easily be able to tell if you can handle yourself transiting a Bravo without ever needing to put you inside one. Same thing with the examiner.
Your radio work and ability to communicate effectively your intentions as well as copy clearances and follow those instructions should be old hat by the Private ride. That's the building block skillsets for operation in a Bravo, a Charlie, and a Delta so the skillset overlaps considerably. If you can handle one, you're 95% of the way to handling them all.
And even if you're flying out of Podunk Nowhere far from any of those, the instructor can (and should) simulate talking to you like ATC would, from day one. And be teaching what the phraseology means and how to copy it and follow it.
It's actually one of the easier things to teach and easy to reinforce. Just give the student a heading and an altitude to fly on takeoff just like a controller would, "cessna 123 cleared for takeoff at pilot's discretion, fly straight out, climb and maintain 3000". Student responds to instructor just like they would a controller.
And in the practice area, all turns, climbs, or descents are preceded with a "clearance". Not "let's turn right about thirty degrees", but "Cessna 123, turn right heading 260". Same readback.
When arriving to land, reinforce the "Are we cleared to land?" question even at an uncontrolled field. The landing "clearance" is assumed but the PIC still asks in his or her head and surveys the environment before giving themselves said "clearance". "Cessna 123, descend at pilot's discretion, cleared to land at pilots discretion..."
It's the instructor's job to make it real. See how easy that is?
Obviously once the student is comfy doing that with the instructor, all thats left is to tune the right frequency from the chart and push to talk and release to listen. (And yes, after nearly 20 years of teaching people on the ground to talk on two way radios, you have to say that second part. Otherwise one in five will leave the mic PTT button keyed after they talk. No kidding.)