Inosuke doesn't become a Hashira in the manga. The story progresses with him having other significant experiences and achievements instead of achieving that specific position.
It's hard to give an exact number. Different story arcs and battles led to the deaths of multiple hashira. Some died heroically, while others met their fate in unexpected ways. The count changes as the manga progresses.
Definitely not. Genya remains outside the ranks of Hashira throughout the manga. This is because of a combination of factors such as his skills, experiences, and the overall direction of the story.
Another way might be collaborative reactions. People can get together in a virtual or real - space and discuss the story in real - time while it's being told. Each person can bring their own perspective, and the combined reaction creates a rich tapestry of thoughts and feelings about the story.