you know, i had been wondering the exact same thing a couple of days ago, right after watching a news feature on people's reactions to the decison made by the Delhi HC...there were three arguments every person against the move had in common...one of them was this feeble attempt at logical analogy, comparing Homosexuality to Prostitution like they have everything in common, which makes very little sense to me...but that is besides the point, if i am to stick to yor question strictly...
as far as prostitution is concerned, it has also been a very sensitive issue in India...and for a long time too...that is at least one thing shares with Homosexuality as an issue...other than that, it is very different...since while homosexuality is about personal choice, prostitution may not always be so, especially in a country like India...and therefore, it would follow to some extent that before one thinks of legalising it one should first try and assess whether there can be something else done to protect the right of those women who are not into it of their own free will...poverty has been as issue since time immemorial, and i agree that wiping it out is not an overnight process...but if a step is taken to legalise prostitution, it is not feasible for it to be so without additional attention to its causes, and whether it is correct to allow them to exist along with the trade itself...
that apart, the problem also aises of what happens after such a step is taken...one of the main concerns of prostitution, practically speaking, is STDs...and so, legalising it must involve precautions of that nature as well...which, in turn, will include sex-education, condom vending machines, general awareness...see how so many larger issues get connected with it? change, if brought about, cannot be brought about with a unidimensional approach...if the present government is prepared to do that, then there are many things that can be set right, and prostitution is certainly one of them...
i'm sorry about the length...i have a problem with being concise at times...hehe...sorry!
cheers! 😃