On Android user can use back gesture to move up in the folder hierarchy.

On iOS back gesture isn't available, so user is more reliant on breadcrumb experience which isn't great at the moment.

a) Modify breadcrumbs to show current folder, its direct parent and hide behind toggleable: "..." any levels that didn't fit.

At the moment first (Files) and the last level (current folder) is always shown and middle part of the breadcrumbs gets shortened to: "...", upon tap it opens up and creates horizontally scrollable widget, but it starts always from the left (top upward folder) forcing user to scroll right to get the immediate parent.

b) Instead of hamburger icon think of using back arrow on iOS,

c) Consider moving breadcrumbs to a new bar.

Related to a comment: https://discord.com/channels/1069654792902815845/1069654792902815848/1289279239027294279