When Sundar Pichai announced Google I/O 2024 details a few days ago, the internet filled up with speculation of a new Android version and reference device release. It seems like it may not actually go that way according to website Android Geeks. They have been told by an insider working at Google Dublin that there is to be no mention of any Android or Nexus device release during Google I/O. Instead, it will happen during a later event similar to what happened last year with Android 4.3 and Nexus 7 tablet being unveiled two months after Google I/O 2024.
The reason to jump from a 7-inch to 8-inch might be because of less competition. There are countless amounts of 7-inch tablets out on the market today and only a couple 8-inch ones so it makes sense that Google would want to join in. Other than that, not much else is known and it is a rumor after all, so I suggest you take it with a grain of salt and keep yourself busy with MWC starting next week.