Most people don't use salary sacrifice to pay their pension contributions so it will make no difference to most people.
I see this as a better way to increase revenue for the government to now as it won't impact what is in people's pockets.
Stopping NI benefits on salary sacrifice won't make much difference to the amount going into a pension. A basic rate taxpayer will still benefit from 20% tax relief. They will just lose the 8% NI saving, so 8 quid on a £100 contribution. A higher and additional rate taxpayer will still get 40/45% tax relief and will only lose 2% of their contribution, so even less of a contribution hit and still benefitting from the massive tax relief.
There are many businesses out there that also benefit from the NI saving (some are generous and pay the employer NI saving into an employee's pension but most don't), so the government will also benefit from extra employer NI.
To the OP, on 24k, if you have been auto enrolled and you aren't using salary sacrifice it will make no difference to you. If you are using salary sacrifice then it will make very little difference.