Well, it just means train capacity at peak hours is getting very much far over nominal capacity. Infastructure itself can't handle the density of people. The infastructure for the older tracks are technology that hasnt changed much since the standards were set long ago, only more electronic based.
A few solutions:
They say that they need to keep the speeds of the trains to a certain speed of about 75kph is true, as our tracks are considered very heavily used in terms of frequency, not tonnage. Its very important to ensure that the tracks are in proper position since small variations can cause derailment.
Instead of 6 train cars, the standard should be 8 cars.
Means hacking up stations to extend them and the other problem is that 6 cars is a standard that train manufacturers provide. (Still possible)
Or instead of using standard gauge rail, use broad gauge rail. FYI: Gauge is the width of the tracks, large gauge can support heavier, bigger trains that can run faster. Standard gauge is 1435mm or 4ft, 8.5 inches wide. Malaysian KTM rail is 1000mm (narrow gauge).
Means hacking up tunnels (near impossible now) to widen them. Also means replacing trains, special ordering new broad gauge ones since most of the world uses standard gauge.
Improve the signalling system on the older lines to reduce frequency further. The older train signalling system cannot handle faster than 2 mins. (Will need long shutdowns on the current lines)