It's been all over the newspaper media here in the UK recently, and I'd had it shared a few times back in [November?] from my circle of friends. Me being me, I ignored it until it was posted here... .
I'm not familiar with previous versions, but I do think one big reason this one succeeded is the easy ability to share your results (through a simple copy/paste) without sharing specific guesses through emojis, which helped virality.
Also the fact that it's one word a day, same for everyone, so people have a habit of doing the daily word and sharing it. It creates a community feeling. I often discuss the word with my friends like "what word did you start with?" etc after seeing their emojis.
The endless-mode Wordle copycats are just not fun and miss the whole point. I want to do the word and move on with my day, as part of a daily ritual.
Note that the game actually works off of local time, so you might actually have a different word than someone else even if you play at the same time. As soon as it hits 00:00 where you are, it switches to the next predetermined word.
Let's not forget no sign-up/authentication. The session is stored locally, so you keep your stats as long as you use the same phone/browser each day.
Interestingly, this lean design also means the answer is stored locally, but as one commenter observed "Anyone pointing this out would have their mind blown when they learned the newspaper jumble and the answers in the corner upside-down"
These decisions would be terrible for a competitive game where folks are striving to top the HIGH SCORE tables, but are smart for an approachable little daily routine.
