3AC Bengaluru to Mumbai is 1.3k and 2AC is 1.9k. Cheapest economy class fare between Bengaluru to Mumbai i found on Amazon app is 2.1k with average price around 2.3k.
Here I don't find any reason to prefer 2AC of IR over economy class air travel untill and unless you are a railfan but 3AC is still cheaper.
P S. Even I don't support this drastic reduction in SL coaches but i do support maintaining a balance between SL and AC depending upon the route and trains.

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This shows the lack of foresight and mismanagement of IR. One doesn't suddenly increase AC coaches so much overnight or decrease nine SL coaches at one go. I am not sure if they have even checked the viability of the decision they are trying to make. Ideally, both increase/decrease in coaches ought to be done in a phased/timely manner. But IR, apparently, doesn't want to take a logical approach.

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Also had they kept the fares of 3ACE half way through SL and 3AC that would have been fine too.

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Of you need to book atleast 1-2 months before in 3AC/3EC that simply means that these are getting good patronage.

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That will also not be feasible. Total earning of a 3 EC coach will be less then total earning of 3AC coach. Result, in future they need to scrap 3EC coaches as well

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