As long as that anybody has an Apple Macintosh computer, can be bothered to learn Objective C and is willing to pay the $99 dollar annual iOS Developer Program fee.
Nonsense.
(a) Most decent programmers will already know C/C++ .... Objective C is not a major stretch, its a strict superset of C !
(b) It is possible to use C/C++ for the back-end of a program and Objective C for the User Interface only.
(c) Objective C has many benefits (e.g. memory management ... a traditional thorn in the side of many a developer ! )
(d) Swift is even easier to use than Objective C for the first-time newbie programmers
(e) In the grand scheme of things, given the time, effort and money that goes into developing apps $99 is a walk in the park. And for the majority of developers is nothing but a minor business expense.
(f) Nothing stopping you writing Objective C source code on Windows ! You only need XCode for compiling and signing.
Android has lower barriers to entry.
Mountains out of molehills. Barriers to entry are NOT high with Apple.