Things that RCs still need to answer:

• How do RCs generate that demand in the first place? What kickstarts the demand cycle everyone was so hyped about a few months ago?
• RCs limits can apparently be changed when they do not function correctly, what's stopping us from adjusting these limits in the future?
• Do the current limits make sense given the current blockchain? Should we spam to test it out?
• Nothing is at stake for larger users as they have have excess RCs they can sell. You could argue that such a system is fair if it were rolled out with the protocol initially but it clearly favors larger users (which isn't a surprise since they determine witnesses for the most part).

How burning stake addresses these issues:

• creates immediate demand and slows down inflation
• would require consensus and a HF to alter, is simpler to explain, and easier to visualize / theorize about
• combined with bidding + byte market, burning has a natural equilibrium that matches that of the blockchain, it isn't artificially calculated
• everyone pays the same, even the larger users (egalitarian, encourages decentralization)
• CONS: not freemium, maybe user unfriendly

I think a lot of this has to do with the regeneration of RCs. If RCs didn't automagically regenerate and were staked and only given back after meeting specific requirements, then it might work as intended, but in the meanwhile, the only people RCs look to help are large stakeholders granted Steem has a future.