The 0.001 threshold is there for a reason. The platform can't afford to start offering rewards to people who have just signed up. There'll be potential for rampant abuse then where thousands of bots will start upvoting posts.
Newcomers are encouraged to post and comment, earn some Steem Power that way, if they don't want to invest in the platform.
i think something should be done to encourage active users. The Bot question is interesting but the 30 min rule and the voting power rules still helps prevent bot abuse.
Bots can vote after 30 minutes, that's not an issue, and also there can be many bots.
Perhaps more can be done to encourage active users, but I don't think lowering the curation reward threshold is an option.
Bots vote whenever they want - @wang, @jl777, and all their clones consistently vote my posts at 15 minutes.