HTupolev

You can in some cases. 11-speed cassettes with large big cogs can be designed to have the biggest cog overhang the wheel's spokes slightly, so the cassette takes up less room on the freehub. 8/9/10-speed hyperglide freehubs are all the same. Shimano's 11-speed cassettes of 11-34 and larger are generally designed to fit on 8/9/10-speed freehubs.

(It's also possible to machine many 11-speed hyperglide cassettes 11-25 and larger to fit onto an 8/9/10-speed hub, but this is obviously not approved by the manufacturers and will definitely void any relevant warranties.)