I'm not sure about 85% mined, have calculate diff. ?
And what will happen if bitcoin 100% mined

Sometimes I wonder what will happen when all the bitcoins will be mined,like the king of coins will be gone from mining.How will it effect the crypto world then?
Miners will be competing for transaction fees...
I think this could potentially negatively affect the security of the network if not enough people are using bitcon by this time. If TX fees are not high enough then miners will likely not make enough to justify continuing to mine
But, if TX fee is high. People will only send his/her bitcoin if it's important

I think transaction fees are getting lower (seen it on my wallet/transactions, correct me if I'm wrong), but don't forget that by becoming more and more popular, more transactions will (could) take place resulting in a net larger transaction fee per block.
As to whether it will be profitable for miners to compete, would miners need to run TH/s ASICS at that time in the future with huge power consumption? Wouldn't it be more economical to run low-consumption miners? Well then again, depends how much one makes from transactions.
It will always be most economical for miners to run the most energy efficient miners possible. The overall amount of energy consumed does not matter as long as it is efficient in terms of watts per Gh/s. As even the most efficient miners are not able to make enough money from TX fees and block subsidies (when applicable) then the overall hashrate will decline.