Update deletes my launcher (June 7th)
I had to use the custom launcher from Nexus to be able to play at all, but kept a backup version of the original launcher.exe.
For the update, I deleted the custom .exe and put the original back in place. I noticed that I still couldn't launch the game after the update.
I looked into my files and saw that the original launcher.exe was gone for some reason.
Then I noticed how the "repair" option put temporary download files for the launcher into the folder only to not download the file.
I then tried to put the custom launcher into the folder and repair again. And again, Origin wants to download the launcher, doesn't do it but rather deletes the existing file.
It seems that Origin tries to replace the existing launcher file but only deletes the old one without putting a new one into its place.
Well, back to custom launcher it is.
@MetroWinter A number of antivirus programs block Sims 4 by default these days. Sophos is the biggest offender, and it affects the MELE too, but others include Avast and AVG, Bullguard, McAfee... I'm probably forgetting a few. Point is, if you run a third-party antivirus, try disabling it and then repairing: the repair would put back any files the antivirus quarantined. With Sophos, you might have to take additional steps, as described here for Sims 4:
https://crinrict.com/blog/2020/10/add-exceptions-to-anti-virus-programs.html/#sophos