In the first place, you need to at least decipher all these strange characters such as ‘א’, ‘ב’, etc. and be able to distinguish whether something shown on screen is displayed right or reversed. Would you be able to code a Japanese rendering engine (or for other language that you never learned)?
Second, although Microsoft provides a fairly decent BiDi (Bi-Directional) engine, one needs to learn and master it. Not a trivial matter.
Don’t hold your breath…
BTW, which of the RTL languages do you need?