But most have, and even the ones that didn’t take SQE1 have done some other type of thing. So overall the pass rate is not a good metric of difficulty. At all.

Not all – some will be exempt SQE1 due to LPC or being foreign qualified.

People who have taken LPC are exempt from SQE1.

This is good news! I only need SQE2 and it’s a relief to know that the pass rate is high.

No, because it’s not true. There are some routes to qualification that don’t require SQE1 (see SRA website).
What is notable is the SQE2 pass rate for people who haven’t taken SQE1 is much lower than 81%. In one sitting I think it was around 30%. So the SQE2 pass rate for people who have passed SQE1 is, correspondingly, higher even than 81%.

This isn’t really how it works. I took SQE1 in January 2024 and was in this sitting of SQE2 – so not everyone taking the exam was in that 44% that survived SQE1 in July 2024

The 44% cohort just took their exams actually, so their results will be in May. But I take your point.