No, you misunderstood what I wrote and/or made a wrong assumption.Which is akin to 'an anti-magic field suddenly pops up'.
I did, that is why I responded they way I did. You won't believe what is going to happen next!A good DM would have anticipated the use of Wish in such a way,
I've run three adventures at 20th. TPKs the first two, they finally got the hang of high level by the 3rd time. When we do these one-shot high level adventures I go all out. They were slayed by Demogorgon* in one and Tiamat* in another. They defeated Vecna* in the third.Im almost of the view you need to run a game to 20th, and watch as your players ruin your encounters to get a handle on how high level play handles, in order to become a good DM of high level PCs.
*Custom version, not the official versions.