"Expand All" and "Collapse All" buttons on Gantt Charts

I want the ability to collapse/expand at the different levels. An option to +/- at the release, phase, and feature level across all. Depending on my audience, I will have a conversation at various levels. If it is fully collapsed, but I want to get to the feature level, I must manually click through the release ->phase->feature and vice versa.

"Collapse all" is more important than expand all for phases (i.e. reducing a massive Gantt chart )

Thank you for your idea. I am curious, are you looking to expand all releases at once or all phases within a single release? If expanding all releases, would you want to also see the phases expand? Essentially an option to expand everything on the Gantt?