The root of the issue is people choosing they want to die, not that people are able to die

Yes, but sometimes it's best to take multiple simultaneous approaches when solving a problem, and sometimes the root of a problem is hard enough to solve that other approaches end up being more effective, at least in the short term. Means restriction is well-studied and does reduce suicide rates.

There was a point in my life where I chose to die, and the reason I'm alive right now is because I didn't have immediate access to lethal means. Every extra minute that it takes to figure out how to kill yourself is another minute of opportunity to change your mind, and that's what saved me. We absolutely should be focusing on mental health, but means restriction (particularly gun control in the US) is also an important thing for people to understand and consider.

Sure, work on that too. But the most effective measure so far for suicide prevention has been to reduce access to means and methods. This is replicated in many different areas across time.