Current user of Niagara here, it’s just a unique option. You have favorites on a scrollable list (one app per line) and then you can scroll down an alphabetical list of all apps by letter on the side. Plus the optional subscription is $5 a year, which is actually reasonable in my opinion.
I don’t think it’s a given and the dev has a proven track record.
…buuuuuutttt they did move to a much smaller userbase so I wonder how many ads he will need for sustainability.