This sounds more like a lack-of-resource issue than anything else.
I think Columbus is struggling more than we would like to believe. There's lots of mouth, but no as much money to put that mouth is.
As such, increased pedestrian traffic (and bicycle traffic) means an increased need for litter control, more security, infrastructure improvement (wider sidewalks, bike-related infrastructure, putting your money where your mouth is in terms of complete streets), growth capacity for emergency services, etc. - I don't think Columbus can hope to draw the resource to support this kind of growth- the "problem" with downtown is a microcosm of Columbus' overall dilemma. Businesses can't/won't stay open 'cause the people aren't there. They people won't go there because nothing is open after 4pm. And on and on. So it is the same with resource- you need the people to create a tax base and have interesting things happen. You kinda need something to draw the people here, tho- like a farmer's market that is allowed to grow and be awesome or being able to get a taxi someplace and not have it be a huge hassle to find one (requiring a phone call... wtf?)
Some places seem to figure out how to make this happen. Is Columbus one of those places?
Columbus' growth has been slowing since the 1950s (in contrast to a place like Houston which was of the same population size in that era and is now the 4th largest U.S. city). So we're growing- yay! But that growth is on the decline. I think some portion of our growth since the 1960s has been regional relocation from areas like Cleveland, Cincinnati, and such. It's easier to move regionally than it is to move across the country or internationally. We're due an estimated 8% growth rate in the last decade- that's the 4th smallest increase in population growth in Columbus since 1860 and 8% of 750,000 (Houston had a 20% increase- 20% of almost 2 million... again, in 1950 Houston and Columbus were the same place at a different latitude.)
You know- in 1970 Cleveland was the size of Columbus today (and it was larger than that in the prior 5 decades). Cleveland is roughly 63% of the population size today that it was in 1970. It is less than half the size it was in 1960. These things can and do happen in cities- people leave, fortunes change, population growth goes both ways. I expect that our slowing growth will turn into a small consistent population decrease in the next 20+ years. That's the direction of the trend should it continue to slow- why expect that it will slow and not go net negative?
We've got big challenges ahead. I know this Pearl Alley business seems like a potential cause of issues (people won't come/live downtown!) - I actually think this is more of an effect than a cause. It's a symptom of slowing growth and that even despite that growth (which is slowing)- the growth we've attracted isn't very resource rich, but probably more debt-heavy. That's a guess. I would love to see research on the amount of capacity/debt represented by our growth and the spatial location of that on a map. That is, where people live and how much they have/owe for the people who have located here who represent our growth since 1980.