Main page VS Side menu for long flat list of items on mobile

I am looking to implement a mobile / tablet application. It currently has two views: an items list view that shows all the items, and an item detail view which shows more detail about a single item. The list of items is very long and would not fit in one screen (scrolling is needed).

My question is, for the list view, what are the reasons that I should choose a main page view over a side menu and vice versa? What benefits does one provide over the other? How might the context of the application matter?

As an example, a detail view could look like this:

The main view version would look like:

Example of applications that use this type of list view include: Gmail (emails view -> email content view) and LINE (chats view -> chat content view)

The side menu version would look like:

Example of applications that use this type of list view include: Slack (chats view -> chat content view)