Patriot has several available interceptors. It can engage several target types and is considered an area air defense system, and is “point defense” limited only in the case of high speed ballistic missiles or similar.
It is perfectly capable however of taking over the job,from the Ukrainian S300 system, of intercepting cruise missiles and the like in high-risk areas like the Kiev region.
That relieves some of the pressure on the S300 system. That is now better reserved as a counter to Russian manned aircraft.
For several reasons it is not “THE” answer to all Ukraine’s air defense problems. Patriot is too immobile and complex to approach the front lines. It is best used to cover a rear area collection of targets - Kiev, say, or Odessa. It’s also overkill for many engagements. It’s also one of the very few US/western systems deployed in Ukraine that are relevant in East Asia, so there are only so many batteries or interceptors that can be supplied.
Fortunately it is not the only air defense system being supplied. NASAMs and IRIS-T are more point-defense oriented. They are also good for replacing the S300 in the anti cruise missile role.
There are open source documents regarding PAC-3 ballistic missile area defense coverage. In general, a 15 KM circle is the defense area for ballistic missiles, or apprx 175 sq KM. Not nearly enough to defend a city the size of Kyiv, but calling it "point defense" is quite a stretch.
The PAC-2 increases that coverage by a large margin, but even with PAC-2 GEM/T, the Kinzhal is possibly beyond PAC-2 capability.