Currently only bricks and slimeballs have the tooltip, it'd be nice to get it on ender pearls, snowballs, eggs, and any other throwable items for consistency

Well the tooltip was meant as a reminder for addition to vanilla items. It just shows on items that were not throwable and we're made throwable. There is some way to show such a tooltip on many throwable items automatically but not all, especially from mods which might do weird stuff. Still idk if the feature is worth pursuing given those hint tooltips are just meant to be a guide for new players and are meant to be turned off at some point