One that stood out to me:

Some activity appeared intended to “troll” defenders, potentially to generate the perception of foreign influence while investing limited resources in the effort

[...]

It is likely that a primary objective of the identified pro-Russia actors [in one identified campaign] was to build the *perception* of influencing the elections—potentially in hopes of supporting future narratives that would undermine the credibility of the election results [emphasis added]

This is a soviet-style demoralization / media exploitation operation.

These work by muddying the waters of public discussion so as to make it harder for the public to know or reach consensus views on anything.

Here, it allows them to simulteniously be interfering and not-interfering, depending on your personal priors, and as a way to discredit researchers engaged in it.

Not useful directly in its own right, but these create the conditions for long-term public fissures for later exploitation.

It's also one of the things that's become obvious in recent years: the job of elections is not /merely/ to collect votes and correctly count them, but to do so credibly so that the public accepts the result.

In other words, you can "hack" the election in one of two ways:
1. The hard way: actually mess with collection/tally/reporting
2. The demoralization way: don't mess with collection/tally/reporting, but undermine the credibility of it anyway so that people don't believe the outcome.