The legislature always meets in public, but the cabinet always meets in private (laws that protect cabinet secrecy have been around as long as there has been a cabinet, here and in other Westminster democracies).
There are media conferences and interviews that are inherently public, and politicians attend public events, some of which are meetings.
But a large part of the day to day work of politicians is done in private meetings, with civil servants, constituents, and representatives of other public and private organisations.
Does anyone honestly think that a reporter or member of the public is supposed to be able to sit in on any meeting that a politician (of any party) attends? That would be absurd, regardless of which party is in government.
If a constituent or a representative of an organisation has a concern and wants to meet with their MLA (Gary Coons is very approachable) or a cabinet minister if they happen to be in town and have some available time, does anyone honestly think they’re going to say, hang on, I’ll have to call the Northern View and put up a notice in case anyone in the public wants to sit in?
Referring to closed or private meetings as “secret” as if that implies wrong doing is misleading.
The issue with Bell Belsey is that as a former politician, and unlike the rest of us, he has to be registered as a lobbyist before he can attend private meetings with politicians, and he is potentially subject to censure and a fine if he failed to do that. But that’s more of a problem for Bill Belsey than for Pat Bell.