Which part? This is a report identifying breaches from a specific group (APT29) and the relevant signatures to detect them. They are releasing this to warn private companies of breaches.

I don't see how it's a "joke" to release a report that could benefit the security posture of an organization. Isn't that what our governments' cyber security groups should be doing?

This time it's quite different that blaming another state for the result of the election you may not like. There is some significant evidence, there is a motive, and I dare say you can't really declare it a negative action in this case. If in this way they can save lives (even one!), good for them.

Did "Russian Hackers" meddle with the UK election too? Because this report is from the UK NCSC, not the NSA or US equivalent.