There's no answer to the question "is Park Hopper worth it" other than "it's worth it if it's worth it to you". It depends completely on your preferences.
In my case, we ALWAYS got PH until our most recent trip (more on that later). We are not big planners and like the freedom that PH allows. (However, with the advent of MDE and electronic FPs, that freedom is getting lesser, but that's another story.) Also, we are not early birds and often hit the parks between 11 and noon. If the park we're at closes at 8pm, we like the freedom of being able to leave and go to the park that has later hours.
I will say that as we have gotten older, we've tended to hop less. In our 30s we would go go go...staying out every night at the park that was open latest. Now, in our 40s, we might only hop for a few days of the trip.
On our last trip we decided not to get PH, for two reasons. One: to save money. It does add a significant cost to your tickets. Two: we wanted to try to have a more relaxing time and thought not being able to hop would be like enforced relaxation. To be frank, I hated not having PH. We ended up not going to HS at all because we couldn't justify using up one whole day's ticket on a park where there's nothing to do (we don't do TOT or RNRC for health reasons, so there is literally nothing for us to do at HS). There were a few days where we definitely would have moved to another park if we had been able to.
To me, the benefits of PH are as follows:
- PH lets you spend a shorter amount of time at any given park
- you can go to "half day parks" without feeling like you've wasted a day of tickets
- you can move on to another park for meals
- you can pop into a park for one specific thing
- you can maximize time by starting at the earliest-opening park and moving to the latest-closing park on any given day
- you can leave a park if you're not into it, and move to another one.
So, for me, definitely worth it. But it completely depends whether those things are important to you. If you're a big planner, you could easily get away with one-park-per-day without feeling like you've missed out on anything.