The InnoDB monitor counter log_sys.n_log_ios was almost removed in
MDEV-14425. This counter was rather meaningless already since MDEV-21534 introduced a redo log group commit mechanism, and on the persistent memory interface there are no file system calls that could be counted. With MDEV-14425, the only case when the counter is updated is when the log file is being read during crash recovery.
Some related InnoDB monitor output in log_print() as well as the information_schema.innodb_metrics counter log_num_log_io are best removed.