Interesting insight. I didn't notice that it was missing. (I wonder if there was not enough room in the flash memory for both this and the new MakeCode stuff - or maybe it was just an accident).
I managed to find a hack to get the Brick Datalog program loaded again.
- Download this zip file.
- Unzip the file.
- Open
Brick Datalog.ev3 in the EV3 programming software.
- Download the project to your EV3.
Open the Memory Browser.

Browse to the Brick Datalog project, then click Download.

Select the Brick Datalog.rbf file (from where you unziped the file in step 2) and click Open.

Close the Memory Browser.
- On the EV3 brick, you can now browse to the
Brick Datalog project and run the Brick Datalog program (it won't be with the rest of the "apps" as in previous versions of the firmware).
How it works:
The brick apps use the same format as user-created programs on the EV3, so I just took the Brick Datalog app from the ev3dev lms2012-compat project (which is identical to the official LEGO version, but easier to get to). Then I created a new empty project in the EV3 Education software and imported all of the images and sounds. The software doesn't let you import .rbf files (the actual program), which is why it has to be downloaded separately via the Memory Browser.
I haven't tested this extensively, but it does seem to work.