I had previously visited the Verona WHS, and the below is only about my experience at one of its components, Arena di Verona, in summer 2022. 

It just sounded fun for me to attend the annual Arena di Verona opera festival and to watch its signature production of Aida composed by Verdi and directed by Franco Zeffirelli. So I bought a ticket for summer 2020. The festival was cancelled due to covid, and the full production of Aida was finally mounted again this summer in 2022. With my ticket I was able to just change the date of attendance from 2020 to 2022. 

I chose a seat fairly far from the stage not just because the ticket was cheaper, but also because I wanted a good view to observe this large production.

Now straight to the point. It was not a very good experience. What was the problem? First and foremost the problem was the sound. I should have known better. Roman amphitheaters (amphi- means circular) were not designed for performing arts. You know what they were designed for. For performing arts, the Greeks created Greek theaters, the Romans actually succeeded them and even built one right here in Verona, that is Teatro Romano.  And there is even an opera festival at Teatro Romano going on concurrently!

No matter how many singers they brought on stage, which numbered several hundreds at times, it did not sound right. Then you can imagine what arias sounded like... I do not believe sitting closer to the stage would have made the sound much better. 

I saw a play at the WH Epidaurus Theater in Greece, but I would imagine musical performance there should also be quite outstanding. 

Although this summer was the 99th season of this festival, and the festival itself has created a reputable history (like Maria Callas made her Italian debut here), I'd say the production was a pure eye candy and the festival is for entertainment purpose only. Then, no wonder Franco Zeffirelli is the best known director at this festival while his mentor Luchino Visconti, the most important opera director at the Teatro alla Scala di Milano (as well as one of the cinematic giants of the 20th century), never directed an opera at the Arena di Verona.

Therefore, I have concluded that, although the set of Aida (photo) evoked the Abu Simbel Temples that played a major role in the formation of the idea for the World Heritage at UNESCO, producing this annual opera festival at this amphitheater is a misuse/abuse of the WHS!