I still think it should be possible to search on Mastodon for any post you've specifically loaded in the last 24 hours. I cannot conceive what the privacy downsides of that would be.
I guess at least we can bookmark here...I'm also on Bluesky, and with no bookmarks there I find myself either missing stuff completely, or doing screen grabs of any post with links or content I don't have time to read/watch/listen to at the time, then flicking through pics later to search for specific handles to find them again... 😬