You are absolutely right: you cannot ever completely take the whole matchmaking and dating and getting to know each other part of real life dating online.

But that is not the point I see in online dating. Online dating shall in my view replace the chance encounters, the host of the parties, the finding out about commonalities by going to the same sports event etc. Having a picture and some basic data will enable you to find some stuff to talk about - afterwards people will probably tend to 'take it offline' anyway for all the reasons you gave.