Maybe because it's spelled "aptoide", though I'd think most search engines would be able to work it out without the missing "e".
Actually I don't wholly trust aptoide - whatever claims they make about safety now they've been too lax in what they allow on their site in the past for me to ever feel comfortable with them (I don't generally belong in the "don't forget, don't forgive" camp, but computer security and politicians' actions are two exceptions). I've not found the app in the sites I trust more though.
But TBH those screen shots look ancient, so it's possible that the reason this app is no longer in the Play Store is that it doesn't meet the minimum API level requirements. Which also means it's possible that it won't work on a more recent device. Of course it's also possible that there was a different reason it was removed from the Play Store.