Fees need to adapt to the ever changing reality of the system and could not possibly be forced or determined through any algorithm.
The Blockstream plan is to FORCE a particular capacity, by setting the block size limit in the consensus rules, and then let the fees "naturally" adapt to that artificially constrained capacity.
Why is that better than forcing the fee directly, and ensuring that the capacity is well above the demand? (I ca think of several reasons why it is much worse.)
Is it possible that the devs do not see that their plan is just as "ideologically impure" as setting the fee directly?
Blocksize limit already exists in the consensus rules, nobody from Blockstream forced it into them.
Again, "fees need to adapt to the ever changing reality of the system and could not possibly be forced or determined through any pre-determined algorithm."
It is better because the block size limit also serves an anti-spam function and a "check" on inherent economies of scale within mining which, removed, would necessarily lead to a precipitated centralization of mining. Regular users running nodes would lose their ability to keep up with the required resources to maintain their access to , and therefore decentralize, the governance of the system.