"the implementers have tended to appropriate Lispy syntax"

But doesn't it make sense that, once you're extending a Lisp dialect to add some Prolog implementation, you'll keep using the Lisp syntax?

I don't see it a question of lazyness or love: one of the main point so many people accept to deal with Lisp's seemingly crazy parentheses is homoiconicity.

It's not that parentheses are that great and that we love seeing: ))))))))) or )))]))]))) (in Clojure).

It's that the benefit (homoiconicity) far outweight the cost of using that syntax.

Because Prolog and Lisp are really quite different. Have you used Prolog for a significant project? Its resolution and backtracking capability can be very powerful for some problems, and you'd have to implement them in Lisp.

I read the sources of an algorithm-derivation system that was done in Prolog (you give it some model relationships and it pattern-matches to find a learning algorithm to fit model parameters to data). It was quite elegant and got a lot of power for free.