Air carrier flight crew reported hydraulic system malfunction in cruise flight.

Narrative

In Cruise flight at flight level 340; received ECAM for hydraulic yellow reservoir low level. Completed the ECAM procedures; checked for follow up in QRH; contacted dispatch/maintenance to discuss best course of action. I decided that a divert to ZZZ was required. Aircraft would have only single reverser; 40% of ground spoilers would not work; and nose wheel steering would be inoperative after landing. I chose ZZZ because it has long runways; and I knew my landing distance would be affected by the failures. The diversion was made; the landing was completed. Airport Rescue and Firefighting (ARFF) was on scene and looked over the aircraft. We were then hooked to a super tug to be towed to the gate. While crossing the boundary from Ground Control to Ramp Control; the escort vehicle leading the tug stopped at the ramp entrance; and the tug carrying the aircraft was unable to stop and hit the escort vehicle. No damage was noted by me; and I believe the collision speed was less than 1 mph. Upon arrival at the gate the Aircraft Maintenance Logbook (AML) was filled out for the yellow hydraulic failure; and the collision with the ground vehicle. Approximately one minute after I received an ECAM for the low hydraulic level; the flight attendant called me to notify me that we had a passenger that was having an 'anxiety attack'. There was weather in the ZZZ1 area and we had light to moderate turbulence for approximately 40 minutes during the climbout. This was also my First Officer's first trip off OE as a new hire pilot. Several causal factors played a role in the event. 1) Widespread convective activity in the ZZZ1 area gave us a pretty rough ride; which was concerning enough for at least one passenger to become distressed. This did not have any relevance to the rest of the event except that it was distracting to deal with during the course of the event. 2) New hire FO. This trip was the First Officer's first trip off OE at Airline X. The event occurred on the third leg of the trip. He is an experienced pilot from Airline Y and did a fantastic job. 3) Dispatch/Maintenance. In making my decision to divert to ZZZ; I contacted dispatch and Maintenance Control to confer about the issues. Dispatch told me that operationally; they would've preferred the aircraft to be in ZZZ2. I decided to divert to ZZZ because I could not justify flying for another two hours; and then [request priority handling] because of the landing distance issues. 4) After landing process. I had let Dispatch and Maintenance know the nature of the [problem]; and that we would need to be towed off of the runway to the gate. After ARFF looked over the aircraft; Maintenance showed up in a pick up truck with gear pins and were told that they just needed to pin the gear and I would taxi to the gate. I informed them that I had no nose wheel steering and I would have to be towed with a tug. The whole event from landing; to getting a tug; to removal from the runway took approximately 20 to 30 minutes because the tug was not waiting for us when we landed. This tied up the runway in ZZZ while they were doing instrument approaches. To me it just seemed like there wasn't adequate coordination done before we got there.I don't believe that there is anything that could've been done to resolve the hydraulic issue; but I do have some observations about things that may be would've been helpful. 1) I've been involved with two [priority handling requests] in the last six months and it doesn't seem to me that Dispatch is much of a resource. I generally have the expectation that I'm calling them to help me with my issue; but I think that I've learned that I need to have a course of action decided and just tell them what I'm going to do. 2) When we arrived at the gate; there was a slew of people in the jetway to meet us; the ARFF event commander; in-flight coordinator; etc. I never got a chance to talk to the tug driver because he had unplugged and driven off and was gone to his next assignment before I got a chance to thank him or discuss the event. The collision was not his fault; and I wanted to let him know that but to also let him know that it had to go in the AML. 3) The Flight Attendants were gone before I ever got a chance to thank them or debrief them. They elected not to continue with their trip and went home; I think in the future I will make sure that I get the opportunity to debrief everybody; but I was so busy talking to ARFF; mechanics; etc. that I never got the chance. 4) I have decided that in the future; if I have to [request priority handling]; once we land; the trip will be over for me. I agreed to swap aircraft and fly the remainder of the flight and passengers to ZZZ2; because crew scheduling told us that once we got to ZZZ2; we would be done and could go to the hotel for the night. Enroute; they reassigned us to an additional leg after we got to ZZZ2. I was to deadhead on the flight to ZZZ; and my First Officer was to fly it. This makes for a very exhausting day when the first leg was a [priority handling event] and erodes the safety margin. The First Officer told me that at Airline Y; it is policy that if you [request priority handling] you are done and are removed from the rest of the trip. Being a new hire on his first trip with Airline X; he didn't have the choice not to do the leg. I will not allow that to happen again.