I don't think anyone is assuming Bitcoin would change its consensus method. Bitcoin is way too much held hostage by the Bitcoin miners and the investments they made into their shiny ASICs. Why do you think we had such a long and tiresome scaling debate in the 1st place?
The current network capacity of Burst is around 100 Petabyte. Discussions about pricing effects in the market were held numerous times and in depth.
Let only Seagate (222 Exabyte) and Western Digital (250 Exabyte) shipped in 2015 together almost 5000 times that much. Even if the network grew 50times its current size each year it would still be less than 1% of the yearly market output and therefore not relevant to pricing. The argument isn't only about efficiency. The argument is also about decentralization. Hard disk drives are a commodity and easily available. No preorders from some chinese ASIC manufacturers. The low energy requirements also make it less problematic if your price per KW/h is higher than there in Cheapenergistan.
Obviously I am talking only about the idealistic aspects. As for monetary or "profitability" aspects - that is a whole different matter. I would not recommend anyone to start PoC mining right now.
Also, I should state, there is a danger that those who are in possession of enormous data-centers may enter the arena and break the market in terms of PoC. There are not so many GPU big players as DATA players(though they are using their spaces just for storage) on the arena, so it may really become a mess.