If that were true (it's not), Apple would be gimping Pages, Keynote, Maps, Preview, Messages, Stocks, Reminders, Notes, GarageBand, Numbers, Mail, Photos, Weather, etc, etc. To, as you would believe, screw their customers.
Try not to go through life believing Apple and TC are greedy and out to screw you. They aren't
And instead realize that Apple's apps are made for the majority of their customers base.
Who are not people who need an RPN scientific calculator that's infinitely configurable and would likely be intimidating to most of Apple's regular customers.
The majority of Apple's customers are regular people; ie teachers, real estate agents, bus drivers, musicians, mailmen, hospital nurses and doctors, car salesmen, gardeners, retail sales clerks, termite inspectors, plumbers, photographers, construction workers, etc, etc. The calculator that Apple includes in MacOS and iOS is perfect for them.
If you're a scientist, engineer, physicist, programmer, etc, etc... simply pay the $10 for pCalc and you'll get an outstanding scientific calculator that will serve you well for 20 to 40 years. Since you already paid $2,000+ for your Apple computer, spending an extra $10 for the best scientific RPN calculator in the world is not out of line.
I don't think it will cause you to go hungry.