The organisation doing the panning is a rail advocacy group, so it shouldn't be surprising that they're not happy with a policy to discount the price of buses without doing the same for trains.
But they're kind of right. Buses are a less efficient form of transport than trains. It's disappointing that they would be making buses so much cheaper to use than trains, and thus incentivising people to choose the bus rather than the train, even in situations where both are viable for the trip, or even the train is the better option.
But of course, this is a Council election, and Council has some control over buses. They have no control over trains. So discounting the trains isn't an option for them. Ideally, the State government would match this by cutting the price of trains as well, but I just can't see it as a bad thing that the price would be cut when our public transport is as expensive as it is.