This regression started in 5.0 major version, could not identify issue where it was discussed/introduced. 

Current documentation page still says that disabled should be displayed and colored in red - https://www.zabbix.com/documentation/5.0/manual/web_interface/frontend_sections/monitoring/latest_data

Debug section shows monitored_hosts=1 parameter defined, strange why.
When selected host (hostid=10324) is disabled, these SQLs are seen in debug section, which look strange.

SELECT h.hostid,h.name,h.status FROM hosts h WHERE h.flags IN (0,4) AND h.hostid=10324 AND h.status=0
SELECT h.hostid,h.name FROM hosts h WHERE h.flags IN (0,4) AND h.hostid=10324 AND h.status IN (0,1)

I'm pretty sure disabled hosts should be available on Latest data page.