There are advantages to being clipless - it aids in hill climbing and because we can use the entire pedal stroke we use less energy over the same route, and more security in a cross wind (at least to me there is). There are advantages to a good set of BMX or other quality platform pedal - poor quality platforms are not worth the frustration - one less step involved in stopping, wider range of shoes, etc.

There are cyclists who will say that you can't "be" a cyclist without being attached to your bike - but that is of course just silliness. If you want to try it then go for it, but it isn't required. I only do it because all of my riding is in the country. I am fortunate that while I do live in the city, I can ride - or drive - to my beloved country roads very quickly. I do not care for urban riding, but if I DID, I would certainly use my BMX peals rather than clipping in.