The decision on using Structured Text for a programming standard should be decided by those who will develop, maintain and improve the factory equipment programming.
I will admit that Structured Text has its advantages but I usually don't use it unless the algorithm can be written easier and more efficiently. You will form your own opinion of ST rather quickly after you start using it.
You can develop any subroutine in RS5000 with ST. That is of course if you paid RA for the license. This has been around for quite a while and it is NOT something new with the L62 platform.
Try it out for yourself and form your own opinion. The combination of using Ladder, Structured Text, and Function Block all have their place in the programming world. Some prove more useful and more efficient based on the actual application.
Maybe the use of Structured Text as a 'standard' is not the real way go, but rather use it as another useful tool to improve (and help) your programming tasks. To set your 'standard' with only one programming structure (ST in this case) may end up as a real limitation.