I think this sidesteps the underlying intuitions too quickly.

I think you are right. I also seem not to have conveyed quite the same position as the one I intended. That is:

• Quantum Suicide is not something that you "Believe In" but rather a preference that in all worlds in which you don't win you are killed.
• This is a valid, coherent and not intrinsically irrational goal.
• You don't get more "winningness" by killing yourself.
• The Everett branches in which you are killed are just as real as the ones where you are alive. They are not trimmed from reality.

These are the points I have found myself wishing I had a post to link to when I have been asked to explain a position. Going on to explain in detail why I have the preferences I have would open up another post or three worth of discussion of whether existence in more branches is equivalent to copies and a bunch of related philosophical questions like those that you allude to.