I'm gonna be as objective here as possible but will mostly focus on the perspective of a newbie.
The image below shows what a default account of 15 SP looks like.
With the new Resource Credit implementation in place, a 15SP account can only do at least 19 comments and 100+votes in a span of 5 days (assuming for simplicity's sake that RC is not recharging). This fact alone makes low level accounts somewhat restricted and very limited on what they can do on the platform. Sure it will really reduce spammy contents published to the blockchain but it will also significantly reduce the interaction of what a low-level SP-human-account can do. (At least for the 'current' RC costs for every transaction)
Newbies/Planktons are the ones who need most "interaction" on this platform. Through constant genuine interaction with other accounts they gain friends, support and visibility. That is why with the current Hard Fork, I believe a new user will really have a difficult time on here on Steem. Not only are they battling visibility and be taken seriously by high-level SP users but they are now also battling on how many comments and interactions can do on the platform.
With regards to the Account Creation System using RC's, in theory YES it will really make user account creation much more easy and scalable considering one won't have to pay anymore to get an immediate account. However realistically as what is happening at the moment, creating new accounts using RC are just too expensive that only a few accounts can actually create one without harming their own allocated RC.
I tried claiming an account yesterday using RC and it said I don't have enough RC to do claim an account. I have an effective SP of 1000+, if I can't even create one account for a friend then 99% of the accounts here on Steem who have less than 500SP cannot also create an account for their friends. This is not easy onboarding at all!!! In theory it was great, but realistically it was not at all close to great.
So yeah looking at it at a perspective of a newbie, I really believe that it is now more difficult for them to survive on Steem. I hope that RC costs will go down in the days so that newbies can do more on the platform. A good amount of comments an accounts can do would probably at least 50 comments per day? :) Overall HF20 was good though as it really did reduce the spam and bad behaviour on the blockchain but at the costs of some real-human-user struggling on the platform. :)