The Lisp library ecosystem is not as organized as that for some other languages. But, quicklisp succeeded in giving a good central point and simple access to libraries. Some reasons for the situation are historic, but some result from the fact that there is not a canonical Lisp implementation as for languages like python, java or perl. The commercial Lisp implementations (and most open source ones) ship with their own set of supporting libraries, so you are less dependent on third-party libraries to get stuff done.
But to everyone who wants to get started with Lisp, I can only recommend not to focus on libraries first. Between what the language includes (especially Common Lisp), and what the implementation ships with, you should be set up to do a lot of serious programming. If there is anything, which you cannot do with the default environment and with what you cannot implement faster yourself, then its time to use quicklisp to add the missing pieces. But having written some pretty large Common Lisp programs myself, they tend to depend on only a very few external libraries.
But to everyone who wants to get started with Lisp, I can only recommend not to focus on libraries first. Between what the language includes (especially Common Lisp), and what the implementation ships with, you should be set up to do a lot of serious programming. If there is anything, which you cannot do with the default environment and with what you cannot implement faster yourself, then its time to use quicklisp to add the missing pieces. But having written some pretty large Common Lisp programs myself, they tend to depend on only a very few external libraries.