But also.... How come they can be Steem Curators since that is the case.

If they can, those being in a powerdown or who did a powerdown in the past few months can be a Steem Curator too or am I mistaken?

It will be extra work to check this manually before voting.

There's also another question: should Steemians always keep powering up?

Many never vote for others, no matter if they have 20 SP or more.

There's also a group only self-voting or voting for two others. Should they receive support?