Looks like they plan to have the blue line extension ready to go in 2029 mentioned in the embedded video not the article.
The plan is to have 55% of the population within 800 meters of public transportation stations by 2040.
A little bit old, but I always like to watch the video linked below: Youtube - Dubai Progress by MetroCucumber
If I had to guess, the Dubai Master Plan from the 60s was probably car driven. They have to break down a lot of structures to create the metro, as well as the New Etihad Rail.
The comment about the app is more to explain the difficulties in using public transport in 50 degrees celsius if you had to wait at a bus stop.
I don’t know many rich people that take the train, so I don’t think it is specifically aimed for them. There is a first class cabin, but it is very small in my opinion.
The train does go through a lot of the richer areas yes. But I think that is mostly to get people to their places of work there.
If you are a solo traveller, the metro is a cheaper alternative to driving.
Unfortunately, here the transport card is still a must