I’m just speculating, based on the information you’ve posted, but if ocean shipping containers from India can arrive in Western Europe so much faster than China already, wouldn’t their geographic location and the fact that the trains will cut down transit time allow India to compete with China in terms of how quickly they can ship goods to Western Europe?
If rail cost has to be 10 times cheaper to match cost with shipping, and rail freight from India to the UK takes as much as 2 days, that’s still only 10% of the regular 20-day shipping time it takes shipping containers to get from India to the UK, so they can theoretically achieve 10 times the profit margin with rail that they can with shipping containers.
The goal is not to make rail freight as cheap as ocean freight, the point of the proposed initiative(I believe) is that India will be able to get their products over to Western Europe in a cost-effective manner that can compete with China, and if their production/export infrastructure and capacity were to reach parity with China, by benefit of geographic location India will be able to deliver goods to western europe faster.