This is what samsung support said about it:
We kindly inform you that we have received an answer regarding Samsung Free because the 'Read Tab' is no longer on the app from the department in charge of Samsung Free.
First, tabs in Samsung Free may vary depending on country, carrier, device, and OS.
Starting with the S24, the Samsung Free Read tab is no longer supported.
Please note that tabs are constructed by comprehensively considering the characteristics of the content, national laws, and technical support.