they got themselves into all sorts of problems with their columnist strategy over the last few years - basically giving space to a whole host of people who simply didn't/don't have the political insight or journalistic experience to justify being published alongside their heavyweight columnists. This skewed their coverage and damaged their reputation overall,
This is very true. It started when they launched Comment is Free - previously the website just published columns by people who were already writing for the print edition, so established heavyweights like Polly Toynbee and Simon Jenkins, and a few people who were prominent in public life - MPs and so on. I remember very clearly a journalist friend of mind saying when CiF was launched that the Guardian would do itself enormous reputational damage, and so it proved. The site massively expanded the opinion pieces it was publishing, and anyone could pitch an idea, have it commissioned, knock it off in their lunch hour and be paid £90. (When I say "anyone", in practice so many people pitch ideas that it's not that easy but they have chosen to commission some complete nonentities without a single original thought in their tiny brains.) And this is why the Guardian comment site now features opinion pieces from people like Owl Fisher and Ash Sarkar, but not, say, people like Professor Selina Todd or Jane Clare Jones, brilliant writers who know what they're talking about.
I hope the Guardian is finally waking up to the damage this has done them and is starting to rethink.