In the case of Steem though, more than 50% of the inflation is going to people who not necessarily have a stake in Steem (authors) via voting. Stakeholders do get a small part of the inflation; 15%, but which is still not a lot.

Sorry, but everyone has to have staked STEEM in order to be rewarded: authors, commenters, upvoters (curators) and even passive investors. Nobody can be rewarded in those four categories without having a stake. The active stakeholders, known as vested, are in the first three categories; the "interest" goes to everyone, be they vested stakes or not.

Funnily, witnesses do not have to be vested but they are paid in SP which automatically is vested.

However, you are right in the overall analysis that inflation is very high. However, because so much STEEM is not vested the real interest rate on an upvote is some 21% APR - a lot more than the approx 8.5% coin-creation rate.

Lowering the coin-creation rate will not change the differentially higher upvote interest-rate unless there is also a substantial increase in activity. And that activity must be rshares-generating activity, not just transfers and JSON activity.

That is the problem I see. That all these new tokens may (possibly) increase demand for the underlying STEEM but the admins of such tokens need to think hard about how to use the Steem blockchain to give value to those tokens especially if the activity on their websites or dapps do not register as rshares-generating activity.

The solution: dapp owners need to think hard how to give their tokens STEEM value.

{edited for clarity!}