FT has the numbers:

Repelled by the direction that both the site now called X and its owner have taken, an exodus from the platform is under way. That exodus — oh go on then, Xodus — has been particularly apparent in Britain, having gathered steam since Musk started posting things like “civil war is inevitable” during the riots that broke out over the summer. Many have left the platform entirely, while others merely lurk. “I have an answer to this, but discussion only on Bluesky these days am afraid [sic],” I saw someone reply on X recently.

Data from Similarweb shows active daily users in the UK have dropped from 8mn a year ago to only around 5.6mn now, with more than a third of that fall coming since the summer riots.

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As disillusioned X users become, yes, ex-X-users, they are finding their way on to alternative sites. With Mastodon having proved off-puttingly techy for many, that tends to either be Meta’s Threads app, or Bluesky, the platform that Twitter founder Jack Dorsey helped to start. But while the former is winning in terms of absolute numbers — about 1.4mn daily active users of Threads in the UK, compared with just over 100,000 for Bluesky — it is the latter that has grown the most rapidly over the past six weeks, and that is cementing itself as the top choice for media types, policy wonks, academics and the broader chatterati.

Although they have to make it weird:

That there is a new place for such people to congregate is all well and good, but the problem is that the chatterati — very nice and non-conspiracy-theorising and non-overtly-racist though they may be — tend to coalesce around some quite similar viewpoints, which makes for a rather echoey chamber. I’m not sure I have ever felt more like I’m at a Stoke Newington drinks party than when I’m browsing Bluesky (including when tucking into Perelló olives and truffle-flavoured Torres crisps in actual N16).

Before carrying on:

An even more fundamental problem is that nobody on Bluesky seems to actually mind that they are in an echo chamber. When I told a friend, who happens to be an enthusiastic Bluesky user, what I was writing about this week, she replied “oh yes, but it is an echo chamber, that’s what people like about it, it’s lovely”.

Many enthuse about how like “old Twitter” Bluesky is, which is telling in itself: in the old days of Twitter, progressives far outnumbered their conservative counterparts in terms of how much they posted about politics on the platform, but that share has fallen dramatically since Musk took it over. According to the British Election Study, in the run-up to both the 2015 and 2019 elections, about 30 per cent of the most progressive Britons posted about politics on the platform. This year, while the most conservative Britons remained no less likely to post than before, the share of progressives posting on X had halved to 15 per cent; presumably that has since fallen much further, given that this survey preceded the riots.