Since 4.7.x (I think) the ctdb command has changed such that many operations are now unable to produce proper machine readable output. This means that the contributed Nagios plugin in the source tree no longer works.
Even with ctdb -X scriptstatus the fields are not whitespace separated (and the date and time fields also contain spaces) which make it much more complex to interpret the results programatically.
Ideally all "ctdb -X" commands should return colon-separated fields as previously or the nagios check should be rewritten to parse fixed-width fields.
ctdb command is primarily designed to for user-interaction with ctdb. It never produced machine-readable output consistently for all commands.
So it's a design choice to avoid generating any machine-readable output from ctdb command in future.
The real fix is to rewrite nagios plugin using client api instead of trying to parse output of ctdb command. Unfortunately the nagios plugin is contributed code and not maintained by the core development team.
We might fix the nagios plugin, but it's not a priority.