In stack traces posted to
MDEV-25773, we can observe that DROP DATABASE (or DROP TABLE) would end up waiting for the buffer pool mutex, for allocating a page so that the to-be-dropped table could be opened.
This is unnecessary and could cause a crash, in case the data file is corrupted. In
MDEV-21069 we already removed writes to the .ibd file on DROP TABLE. There should be no need to read the .ibd file either.