Service script /usr/local/etc/rc.d/minio needs a REQUIRE line at the top.
I run minio in a jail and when the jail is restarted, minio does not start due to the network not being available until later in the process. In my specific case, my jails use VNET with synchronous DHCP. Once the jail is running, I shell into it and start it manually.
I haven't fully investigated yet, so not sure what exactly is required, but using "# REQUIRE: DAEMON NETWORKING" worked.