With these new rules I dont think airlines and operators of 1900's and the like will require applicant's to have a full ATPL. Having the subjects should just be enough.
With the required experience on type after flying as FO they will just do your ATP test during an IF renewal. Any half decent company would in anyway pay for your 6 month recurrency's and IF renewals, so the ATP test can just be sloted in when required.
If you pitched to an operator with an ATP and a brand new Embraer Brazilia rating he's not gonna put in the left seat anyway. You'd have to do at the very least a few hundred hours on type before upgrading. So in effect it shouldn't affect the guys too much, thats as long as the operators dont insist on a full ATP licence to employ guys as FO's.
In the past, you could have flown 172's for 1500hrs, do a bit of twin flying, then test on a Seneca and you would then hold an ATP allowing you to be PIC of a complex pressurized multi crew turbine aircraft flying schedule passenger routes in all weather conditions. Now that did not make sense! So i do think these new rules make sense, but the industry is gonna have to change the way it hires new pilots and not expect them to fork out tens of thousands of rands for an ATP test!