Hi,
Based on my understanding, I can confirm that simulink follows causal modelling standards & simscape (along with SimElectronics, SimHydraulics, SimMechanics) is an example of acausal modelling.
In causal modelling, relation between different blocks is solely defined by the output of one block being fed into the input of another block.
In acausal modelling, parts of system are described through equations where output of a block is not defined from input given to it.
Hope this helps!