Any PoS shitcoin is capable of low inflation. That doesn't automatically translate into a higher market cap.

Sure, it does not mean that this will happen automatically. But it does shift the supply curve and would thus result in a higher price - all else being equal. How much higher - this would need to be seen.

I would be surprised if Steemit, Inc were still selling at the rate it was before February. Three of the most highly paid employees of Steemit, Inc quit: all the developers they had on board as well as the head of communications. As far as I know, they haven't hired replacements.
I was mainly referring to the period before Justin Sun appeared on the agenda. And even though there costs might have been lower, I would think that they still sold on an ongoing basis to liquidate their stake. But this is pure speculation of course.

The only people benefiting from a lower inflation but higher token price would be the current whales.

Unfortunately, there is still a lot of circle and buddy voting - so I am not sure on that. If all the inflation would go to good content producers, I would be with you. I am afraid, though, that this is not the case.

Consider the fact that STEEM went from 7 cents to $8.5 from March 2017 to January 2018.

This is for me a sign that the supply curve of Steem and now Hive is rather flat as supply is rather flat. Either people sell at any price anyway or they do not sell at all as their Hive is powered up. This shows me that a small shift in the demand curve might result in a huge price increase.