primal is quite algorithmic in its design:

- there is fixed list of influencers on the right

- default view uses some algorithm called "highlights".

- other algorithmic feeds are popular and trending. these keywords do not clearly state how these feeds are generated

- other algorithm style social influence system is predefined list of followings. primal adds by default ~60 influencers to your following list when you register

- primal global feed probably have some filter. i have never seen my note on global feed.

coracle

- coracle default view for guest account (not signed in) is follows. this is absurd, as guest account does not follow anyone.

iris, snort

- default view for guest account is popular. this naming does not reveal what algorithm is being used

note that these popular feeds are not based on just number of likes. you can see this for example by checking primal popular feed, and seeing that they are not sorted by number of likes alone.

WoT scores:

at least coracle have done some testing based on WoT score. previously stated predefined set of profiles followed will affect any of these results. also any WoT score based systems introduce feature called social bubbles.