I don't know, some people may find buiding a structure that costs 72 iron/steel and in regular circumstances requires nether materials. (If you settle for a smaller boiler this cost can be smaller and certain mods can make blaze powder pre nether)Gameplay.
Railcraft wins hand down for doing something interesting to produce a useful result rather than the plug and play simply handing it over on a silver platter.
Some may find a magical steam box to be a more satisfying option. Building a multiblock and waiting for heat up might be anti gameplay.
However I think saying there's no point to RC boilers is silly considering they where the first to do the whole steam thing.
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