I remember Lawrence Miles really went off on The Unquiet Dead on his blog. He truly didn’t like that story.
I think it’s unfortunately in the nature of ’alien invasion’ stories to have the potential for xenophobia– it’s built into the trope at the level of ’alien beings = evil’. That being said I’ve also seen reading of the trope through an anti-colonialist lens. I think it depends on how sensitively the writer approaches the topic.
I still think there isn’t a huge amount of harm in doing a ‘what if the fears are right?’ story or at least extrapolating those fears to an extreme conclusion. It’s what science fiction does.
They’re not fears I agree with but no one is giving Nigel Farage a copy of Flip Flop and telling him he was right all along because Doctor Who says so.
I think writing a twist on an alien invasion where the aliens manipulate the population of the planet is a perfectly valid narrative choice. Where it maybe goes wrong here the amount of ‘this is what the refugees will do if we let them take over’ rhetoric put into the mouths of the Slithergees.
I do think it’s a bit ‘have your cake and eat it’ to dismiss The Unquiet Dead though. It clearly shows the Doctor being duped by ‘refugees’ and could quite easily be critiqued in the same way as Flip Flop is. They’re both versions of the same trope really.
Maybe I’m naive but I like to think that most Doctor Who writers aren’t setting out to promote dangerous political ideas and that most of the time it’s just an unfortunate combination of story elements, audience bias and the change in cultural and societal awareness which makes older stories hit differently. It doesn’t make the people behind them terrible human beings.
Oh I did not enjoy this. I found the format rather confusing, as there doesn’t seem to be any real conclusion in this story? Seen others have pointed out too that the two sides were just far too similar also. The xenophobia made for an uncomfortable listening… 1/5
A distant second to Nekromanteia for the biggest duds of the early Main Range. The Slithergee are definitely part of my issue with it (I didn’t clock it as refugee scare material personally, just a more generic yet pointed xenophobia… which still left me uncomfortable), but mostly, it’s just the structure of the thing. The looping narrative is a neat idea, and I like it when BF gets experimental like this, but rather than get all geeky about which one is the ‘real’ ending, it just left me feeling like the story didn’t even have an ending.
Unlike Nekromanteia, I can at least get why someone would like this where I didn’t, what with its cribbing from Back To The Future and Groundhog Day. I don’t even see it as all that malicious, as a lot of the more problematic messaging with Doctor Who usually comes from two ideas sitting next to each other that, while innocuous on their own, say some… odd things when put together; it’s accidental more than anything else.
I re-listened to it yesterday.
I think the way the narrative loops around is really cleverly done.
The thing that really sticks out for me is the gag about how his earlier incarnation invented anti-radiation gloves. Way to lean into the “Billy fluff” 
(and it’s done without being condescending towards Hartnell 
)