LTA regulates the public transport operators while PTC plays the
figurehead role. Pretty much like the relationship between the PM
and President.
PTC's role becomes in the spotlight during fare increase time where
they try to "understand" operators' reasons for begging for money,
and justify to the public why PTOs should be given fare increase
despite increasing earnings, revenue and profit.
IMO, LTA should be the rightful party to regulate the transport
companies as public transport falls under land transport
purview.