On one hand, we should be solving this by increasing normal coach trains and having more regular services interconnecting states. Longhaul trains can be substituted with chained inter-state train tickets so that it reduces burden on scheduling of train routes and disburses the crowd on multiple routes.
On the other hand, it's not economically sustainable for the railways to cater to basic sleeper and seater tickets as those are heavily subsidized.
Well the railways ministry recently started converting passenger trains into express trains.
And replacing general and sleeper coaches with AC coaches. That's what caused this problem.
Now even in 2AC people are stuffed like sardines.
Yeah it was never profitable to run sleeper, general coaches and passenger trains. They usually convert the loss into debt or transfer the burden to tax payers.