OK but...Forget miners...There is also costs of buying Bitcoins for Bitcoiners, right?!...Should other poeple supply their costs for buying Bitcoin?..No! This is the cost that anyone should supply himself regarding his pocket size! Otherwise Bitcoin would get worthless! Therefore, there is a cost for any value! and I think that's clear enough....So, lets rephrase your question more reasonably: How can we decentralize the cost of establishing mining farms (capital cost, not operating cost!) for "wider range" of investors? (bcuz not everyone can and should start mining...there are some requirements!)
Answer: Bithority will be able to provide the necessary infrastructure for even capital cost financing, later on, when it can catches enough traction from folks in Bitcoin community. For instance, miners who already have running mining farms for a while, they can get a credit score from the Bithority token holders so that they can apply for financing their Capex of mining. And definitely, as in many financial means, there will be some risks for those lending money per the capital cost (establishment cost) which Lenders should accept and deal with! So you see this can also happen, but this is a solution already been implemented in many lending platforms worldwide and even without Bithority!
As an expert in bitcoin mining that has been consulting industrial scale farms, I can tell you the problem of the miners is not their capex but it is their opex!
When I am talking about decentralization of Bitcoin mining, it doesn't mean every single individual on earth should be able to get into mining but it means we need a wider/diverse range of investors to get into mining with the minimum dependency and effect from governors and states!
As a result, I still claim that Bithority can "vastly decentralize the Bitcoin mining ecosystem"